A perfect season is a sports season including any requisite playoff portion, in which a team remains undefeated and untied. The feat is extremely rare at the professional level of any team sport, and has occurred more commonly at the collegiate level in the United States. A perfect regular season (known by other names outside the United States) is a season excluding any playoffs, where a team remains undefeated and untied; it is less rare than a complete perfect season but still exceptional.
A perfect season may be part of a multi-season winning streak.
Exhibition games are generally not counted toward standings, for or against. For example, the 1972 Miami Dolphins (below) lost three of their preseason games but still are considered to have had a perfect season.
- 1 American football
- 2 Canadian football
- 3 Lacrosse
- 4 Other North American professional sports leagues
- 5 American collegiate sports
- 6 Australian Football
- 7 Rugby league
- 8 Rugby union
- 9 Cricket
- 10 Netball
- 11 Association football
- 12 Team handball
- 13 Tennis
- 14 Volleyball
- 15 See also
- 16 References
National Football League
Since the National Football League began in 1920, only one team has played a complete perfect season (both regular season and playoffs): the 1972 Miami Dolphins, who won their fourteen regular season games and three postseason games, including Super Bowl VII, to finish the season 17–0–0.
The Dolphins briefly extended their winning streak before losing to the Oakland Raiders on September 23, 1973. It has often been reported that the surviving members of the 1972 Dolphins would either gather to drink champagne when the final undefeated team earned its first loss, or send a case of champagne to the team who beat this final undefeated team. The head coach of the 1972 Dolphins, Don Shula, denied this in a 2007 interview with ESPN. On August 20, 2013, four decades after their accomplishment, President Barack Obama hosted the '72 Dolphins noting that they "never got their White House visit".
NFL undefeated seasons (with ties) prior to 1932
Prior to the development of a playoff system in the NFL in 1932, there were four teams who completed seasons undefeated, but with one or more tied games: the 1920 Akron Pros, the 1922 Canton Bulldogs, the 1923 Canton Bulldogs, and the 1929 Green Bay Packers. According to the 2012 NFL Record & Fact Book, under NFL practices at the time, from 1920-1971 tie games were not included in winning percentage so, these four teams were recorded with perfect win percentages of 1.000. 
The 1921 Buffalo All-Americans were controversially denied a similar type of near-undefeated season, when they believed that their final game, a 7-10 loss to the Chicago Staleys, was an exhibition game which would not count to the final standings; the NFL records that game as official, and Buffalo's record as 9-1-2.
Other NFL perfect regular seasons
In 1934, the Bears played a 13–0–0 regular season and became the first NFL team to complete an undefeated regular season without tied games, but lost the 1934 NFL Championship Game against the New York Giants. Despite losing several players and head coach George Halas to military service in World War II, the 1942 Bears finished 11–0–0 but again lost the NFL Championship Game, this time against the Washington Redskins.
The 2007 Patriots became the first team after the NFL expanded its regular season to sixteen games in 1978 to finish undefeated. They won the divisional and conference playoffs before losing Super Bowl XLII to the New York Giants, giving them a final record of 18-1. While the 1972 Miami Dolphins did complete the perfect season at 17-0, the 2007 Patriots did surpass their total by one game with an 18-0 record albeit ultimately losing in Super Bowl XLII.
Pre-NFL era and competing leagues
An NFL predecessor, the Ohio League, had many perfect seasons. The Massillon Tigers (1904, 1905), Akron Indians (1909), Shelby Blues (1911), and Dayton Triangles (1918) all had perfect seasons during this era. In the New York Pro Football League, another league that contributed teams to the NFL, the Buffalo Niagaras went 5–0–0 (6–0–0 including a forfeit) in a league that consisted of teams entirely from the city of Buffalo in 1918. In 1920, the Union Athletic Association of Phoenixville, Pennsylvania (later known as the Philadelphia Quakers), played in a league mostly consisting of local teams and earned a perfect season, claiming for itself a mythical national championship. Prior to the Ohio League, the 1900 and 1901 Homestead Library and Athletic Club teams, as well as the 1903 Franklin Athletic Club, all had perfect seasons.
The caliber of talent was neither as high nor as consistent between teams at the time, the seasons were generally shorter (7 to 11 games), and it was not uncommon for top teams to play all their games at home while lesser teams played all of their games on the road. In 1918, Dayton and Buffalo had the additional advantage of having its strongest competitors suspend operations due to the Spanish flu and the First World War. Thus, it was much easier to earn a perfect season than it would become in the NFL.
1937 Los Angeles Bulldogs
The Los Angeles Bulldogs were a member of the second American Football League, who joined the league in 1937 after the Cleveland Rams defected to the NFL. Playing a combination of AFL teams and independent franchises (such as the Providence Steam Roller and the Salinas Packers), the team went 16–0, with 8 of those wins coming against AFL teams. The Bulldogs’ dominance is cited as one of the key factors in the AFL’s demise, and the next season as an independent with a 10–2–2 record including a 2–1–2 record against NFL teams, several of the team’s players were invited to play on the "Pro All Stars" team in the NFL’s first Pro All-Star Game in Los Angeles. The Bulldogs are considered to be one of the few independent teams to have ever achieved parity with the NFL.
1948 Cleveland Browns
The Browns were a member of the All-America Football Conference, a professional football league that played from 1946 to 1949. In 1948, the Browns won all fourteen regular season games and the 1948 AAFC championship to post a 15–0–0 record. Cleveland’s perfect 1948 season was part of a longer string of 29 straight wins, which stretched from 1947 to 1949 and included both the 1947 and 1948 title games. Overall, the Browns won all four AAFC championship games and were accepted into the NFL when the two leagues merged after the 1949 season.
Neither the NFL nor the Pro Football Hall of Fame recognizes the Bulldogs’ or Browns’ perfect seasons.
Close to perfect
Since the NFL expanded to a fourteen-game regular season in 1961, eight teams have had regular seasons with one loss and no ties:
|Team||Wins||Losses||Playoff results||Final result|
|1962 Green Bay Packers||13||1||Won NFL Championship against the New York Giants||14-1|
|1968 Baltimore Colts||13||1||Won two playoff games including NFL Championship but lost Super Bowl III||15-2|
|1976 Oakland Raiders||13||1||Won three playoff games including Super Bowl XI||16-1|
|1984 San Francisco 49ers||15||1||Won three playoff games including Super Bowl XIX||18-1|
|1985 Chicago Bears||15||1||Won three playoff games including Super Bowl XX||18-1|
|1998 Minnesota Vikings||15||1||Won one playoff game before losing conference championship game||16-2|
|2004 Pittsburgh Steelers||15||1||Won one playoff game before losing conference championship game||16-2|
|2007 New England Patriots||16||0||Won all regular season games and two playoff games before losing Super Bowl XLII||18-1|
|2011 Green Bay Packers||15||1||Lost division playoff game to New York Giants||15-2|
Most of these teams suffered their regular-season loss early in the year and only the 1962 Packers (10-0), 1985 Bears (12-0), and 2011 Packers (13-0) were on track for a perfect season when they lost. Coincidentally, the 1985 Bears’ lone loss came to the Miami Dolphins.
The best start from an NFL team who failed to complete a perfect regular season was by the 2009 Indianapolis Colts, who started 14–0 before losing their final two regular season games to the New York Jets and the Buffalo Bills to finish 14–2. Indianapolis, having clinched the top seed in the AFC, sacrificed its chances at a perfect regular season and instead rested its starters the final two games to protect them for the playoffs. The Colts would go on to Super Bowl XLIV but lost to the New Orleans Saints.
Four other teams have started 13–0 before losing their fourteenth game: the 1998 Denver Broncos, 2005 Indianapolis Colts, 2009 New Orleans Saints and 2011 Green Bay Packers. The 1998 Broncos, 2005 Colts and 2009 Saints lost at least two of their final three games but the Broncos and Saints recovered to win the Super Bowl. The 1953 Cleveland Browns and 1969 Los Angeles Rams started 11-0 in twelve- and fourteen-game seasons respectively; both lost their only playoff game.
The following is a list of teams in minor or alternate leagues that compiled perfect seasons of six games or more, including postseason games, with no ties:
- The Hollywood Bears, a member of the Pacific Coast Professional Football League, went 8–0–0 in 1941.
- The Hollywood Rangers were a member of the American Football League of 1944 (formerly the Northwest War Industries League), a short-lived competitor to the Pacific Coast Professional Football League on the West Coast. In their 1944 season, they went 11–0–0 and defeated the PCPFL champion San Diego Bombers (who had also had a perfect season in their league, going 9–0–0) in a two-game series.
- The Charleston Rockets of the Continental Football League won all 14 games of the league's inaugural season in 1965, going on to defeat the Toronto Rifles in the league’s championship.
- The Hartford Knights went 17–0–0 in 1972 as a member of the Seaboard Football League, including a victory over the Chambersburg Cardinals in the league’s championship. The Knights, unhappy with the level of competition (many of the Knights games had margins of victory of 40 points or more), quit the league the following year.
In indoor football, the following teams have had perfect seasons:
- The Quad City Steamwheelers went undefeated in the inaugural season of arenafootball2, accruing a record of 19–0–0 including playoffs and an ArenaCup I win.
- The Ohio Valley Greyhounds of the National Indoor Football League accrued a perfect season in 2003.
- The Sioux Falls Storm of United Indoor Football won back-to-back perfect seasons in 2006 and 2007, winning the United Bowl championship both years.
- The Fayetteville Guard won a perfect season in 2007 in the NIFL.
- The Rochester Raiders won a perfect season in 2008 in the Continental Indoor Football League, but withdrew from that league during the playoffs in a dispute.
- The Baltimore Mariners won a perfect season in 2010 in the American Indoor Football Association.
- The Erie Explosion won a perfect season in 2013 in the Continental Indoor Football league, winning all ten regular season games, a semifinal playoff, and the CIFL Championship.
At least twenty-three other semi-professional football teams have had perfect seasons, seven of them being at least 17 games long. The Chambersburg Cardinals won a record 72 straight games between 1977 and 1984.
There have been no perfect seasons (or even perfect regular seasons) in the American Association, World Football League, United States Football League, XFL, or, to date, the Arena Football League. The United Football League has had two perfect regular seasons, but neither qualify for the list: the 2009 Florida Tuskers finished 6–0, but that team lost the subsequent championship game; the 2012 Las Vegas Locomotives had a record of 4–0 when the league abruptly suspended operations halfway through the season.
The 1933 Providence Huskies (possibly a successor to the Providence Steam Roller) played arguably the most perfect season ever recorded by a professional or semi-professional team: a ten-game season in which they won every game and did not concede a single point during any game.
A true perfect season (no losses and no ties through the regular season and playoffs) has never been achieved in professional Canadian football. Only one team, the 1948 Calgary Stampeders, has completed a perfect regular season.
The current CFL schedule would require a team to win 20 games (18 regular season, 1 playoff after bye week, and the Grey Cup championship) to post a perfect record.
1948 Calgary Stampeders
Under head coach Les Lear, the 1948 Calgary Stampeders completed a perfect regular season with a record of 12–0; they had two wins and a tie during the playoffs to finish with a record of 14–0–1, the only undefeated complete season in Canadian pro history. In the Western Interprovincial Football Union playoff series (a home-and-home series decided on total points) against the Regina Roughriders, the first leg was tied 4–4, and the Stampeders won the second 21–10, to win the entire series 25–14. The Stampeders then defeated the Ottawa Rough Riders 12–7 for the 36th Grey Cup.
Canadian Interuniversity Sport
1975 University of Ottawa Gee Gees
In 1975 the number one ranked University of Ottawa Gee Gees had the first CIS undefeated season. After completing their perfect regular season at 8-0, the Gees Gees won their first play-off defeating the number two ranked Toronto Varsity Blues 14-7. The Gees Gees then demolished the Windsor Lancers 45-6 to win the Yates Cup and the right to play for the national championship and the Vanier Cup. The undefeated season was completed on November 21, 1975, when the Gee Gees defeated the University of Calgary Dinos 14-9, at CNE Stadium in Toronto. That night the Gee Gees became the first undefeated team in CIS and Vanier Cup history. The 1975 Gees Gees roster had a big impact on the CFL. Gee Gee Players from the 1975 team played in the CFL for a cumulative total of 96 years and throughout their professional careers in the CFL accomplished: one Canadian Football Hall of Fame Inductee, one Grey Cup Canadian MVP, two Frank M. Gibson Trophies for Outstanding Rookie Eastern Division, two CFL Leo Dandurand Trophy Outstanding Lineman Eastern Division, twenty CFL and Divisional All-Star Selections, twenty-three Grey Cup Appearances and a total of twelve Grey Cup Rings.
2003, 2005 Saskatchewan Huskies
In 2003 and 2005, the Saskatchewan Huskies completed perfect regular seasons. However, in both years they lost in the playoffs: in the Vanier Cup to the Laurier Golden Hawks in 2005, and in The Canada West Semi-Final To Alberta Golden Bears in 2003.
2007 Manitoba Bisons
A perfect season was attained in 2007 by the Manitoba Bisons, the football squad representing the University of Manitoba, located in Winnipeg, Canada. The Bisons were undefeated in Canada West Universities Athletic Association play during the 8-game schedule. In the playoffs, Manitoba comfortably handled the Calgary Dinos 27–5 in the opening round. The Bisons followed up with a 48–5 defeat of the Regina Rams in the Hardy Trophy and a strong 52–20 showing against the perennial contenders from the University of Western Ontario, the Western Ontario Mustangs, in the Mitchell Bowl. On Friday, November 23, 2007, two days before the 95th Grey Cup game in Toronto, the Bisons defeated the Saint Mary’s University squad, known as the Saint Mary's Huskies, 28–14 to claim their first Vanier Cup championship since 1970, and third overall title. That victory capped their perfect 12 win season.
2010 Laval Rouge et Or
In 2010, the Laval Rouge et Or located in Quebec City, Quebec, Canada had a perfect season of 13–0. They were undefeated with an 8–0 record in the QUFL. During the playoffs, they beat the Bishop's Gaiters 56–1 in the opening round. The Rouge et Or won the QUFL championship and the Dunsmore Cup by a close win of 22–17 against the Sherbrooke Vert et Or. They followed with a win of 13–11 against the Western Ontario Mustangs in the Uteck Bowl. Finally, on Saturday, November 27, 2010, in their home stadium in Quebec City, they won the Vanier Cup 29–2 against the Calgary Dinos, capping a 13–0 season.
In professional lacrosse, the 1993 Buffalo Bandits are the only team to have won a perfect season in the National Lacrosse League. The Bandits won all ten of their regular season games and won the championship in a two-round tournament; the season was the continuation of a multi-season winning streak that dated to the Bandits’ successful run for the previous year’s championship.
In Major League Lacrosse, which began play in 2001, the 2013 Denver Outlaws were the first team to complete a perfect regular season, winning all fourteen of their games. After beating the Hamilton Nationals, the Outlaws had a sequence of twenty consecutive regular season wins despite losing the 2012 championship. However, the Outlaws lost in the first round of the playoffs to the Charlotte Hounds, who had only gone 7-7 in the regular season.
Other North American professional sports leagues
In North America’s three other major professional sports leagues (Major League Baseball, the National Basketball Association, and the National Hockey League) it is almost impossible for a team to play a “perfect” season, primarily because there are substantially more games in the regular season (82 in the NBA and NHL, and 162 in Major League Baseball). The Women’s National Basketball Association’s season has been between 28 and 34 games long, and it too has never produced a perfect season.
It is possible for a baseball pitcher to achieve a perfect season, taking at least one win and any number of no-decisions throughout the year. This has happened 1813 times in baseball’s history, though the majority (1171) were 1–0 seasons, mostly by relief pitchers. The best perfect season belongs to Tom Zachary of the 1929 New York Yankees, who posted a 12–0 record in 119.2 innings. No pitcher has ever achieved a perfect season while qualifying for the ERA title.
In the NBA, the 1985–86 Boston Celtics played a nearly perfect home season. During the regular season they were 40–1 (.976) in front of their home crowd, their only regular-season home loss occurred on December 6, 1985, to the Portland Trail Blazers, by the score of 121–103. The Celtics would also win all 10 of their home games in the postseason, to finish 50-1 at home.
Other professional sports
For other sports leagues for individuals, such as the PGA Tour or NASCAR, a perfect season would represent winning every event in a season. Considering the number of tournaments or races in those leagues, and the fact that each individual faces over 40 opponents as opposed to one, a perfect season is almost impossible. Golf instead considers the Grand Slam, deemed to be the four most difficult contests in professional golf, to be analogous to perfection; since 1934, when The Masters was added as a major, no player has won all four in one year. Tiger Woods came closest, winning four consecutive professional majors over two years in 2000 and 2001.
The three golfing seasons that could be deemed closest include Bobby Jones winning all four majors in 1930 (when The (British) Amateur Championship and U.S. Amateur were still considered majors), Byron Nelson winning 11 consecutive tournaments he played in (and 18 in one year) in 1945, and Woods’ aforementioned four consecutive majors in 2000 and 2001.
Professional motorcycle racer Ricky Carmichael had perfect seasons in 2002 and 2004. In 1997, road racer Tommy Kendall started the 13-race SCCA Trans-Am Series season 11–0, the longest documentable win streak in worldwide professional road racing. In the 12th race, he was battling for the lead on the final lap, but spun out and finished second. The feat would be extremely difficult in NASCAR, because of the length of the season (currently 36 races).
American collegiate sports
NAIA Football Champions
In 1966 Waynesburg College went 11-0 after a 9-0 regular season record. In December 1966 Waynesburg defeated New Mexico Highlands in Albuquerque, NM in the playoff game, and, defeated Whitewater Wisconsin in the Tulsa, Oklahoma NAIA CHAMPION BOWL. This was, and still is a college football rarity. Very few college football teams have won a College National Football Championship (including playoff games) with an undefeated record.
Due to relatively short seasons through most of college football history, the list of undefeated Division I football teams includes dozens of teams. The highest level of college football, the Division I Football Bowl Subdivision, does not use a play-off to determine a champion, instead relying on a combination of polls and computer rankings to choose two teams to play one title game in a system known as the Bowl Championship Series. Prior to 1992, no attempt was made to match up the top two teams in a championship game, further increasing the chances of multiple teams achieving a perfect season. The record for most wins in an undefeated season is 14–0, accomplished in 2002 by Ohio State, twice in 2009 by Boise State and Alabama, and in 2010 by Auburn.
The University of Washington’s FBS record 63 game unbeaten streak included five consecutive perfect seasons from 1909–1913. The University of Oklahoma’s FBS record 47 game winning streak included three consecutive perfect seasons from 1954–1956.
NCAA Division I Basketball
Before the establishment of the National Invitation Tournament in 1938 and the NCAA Men's Division I Basketball Championship in 1939, perfect seasons were more common; each season consisted of fewer games and top teams from different parts of the country might never meet.
There have been 7 NCAA Men’s Division I basketball champions with perfect records:
- 1956 San Francisco Dons (29–0)
- 1957 North Carolina Tar Heels (32–0)
- 1964 UCLA Bruins (30–0)
- 1967 UCLA Bruins (30–0)
- 1972 UCLA Bruins (30–0)
- 1973 UCLA Bruins (30–0)
- 1976 Indiana Hoosiers (32–0)
Another team in the NCAA Tournament era had an unbeaten record and won a recognized national title:
- 1939 LIU Blackbirds (24–0) — won the NIT, which at the time was more prestigious than the newly formed NCAA tournament.
The UCLA Bruins are the only team to have back-to-back perfect seasons (1972–1973) respectively creating a record of 60–0 technically, and all four perfect seasons were under Hall of Fame head coach John Wooden.
The following teams have completed a perfect regular season, but lost in the NCAA Tournmament or other postseason action:
- 1939 Loyola Ramblers (finished regular season 20–0 and lost in the NIT final to LIU to finish 21–1)
- 1941 Seton Hall Pirates (finished regular season 19–0; lost in the NIT semifinals to LIU and third-place game to CCNY to finish 20–2)
- 1951 Columbia Lions (finished 21–1 after losing in the first round)
- 1961 Ohio State Buckeyes (finished 27–1 after losing in the championship game to Cincinnati)
- 1968 Houston Cougars (finished regular season 28–0, then lost the semifinal and consolation games at the Final Four)
- 1968 St. Bonaventure Bonnies (finished regular season 22–0, lost in regional semifinals)
- 1975 Indiana Hoosiers (finished regular season 29–0, but lost to Kentucky in the Mideast Regional final)
- 1976 Rutgers Scarlet Knights (finished regular season 28–0, won 3 more games in the NCAA Tournament to go to 31-0, but lost in the Final Four to Michigan and in the consolation game to UCLA)
- 1979 Indiana State Sycamores (finished regular season 31–0, but lost in the championship game to Michigan State)
- 1979 Alcorn State Braves finished the regular season with a perfect 27–0 record, but were not invited to the NCAA Tournament. The Braves lost in the second round of the National Invitation Tournament to Indiana.
- 1991 UNLV Runnin' Rebels (entered the tournament 30–0, but lost in the Final Four to eventual champion Duke).
- 2004 Saint Joseph's Hawks (finished the regular season 27–0, lost in the first round of the 2004 Atlantic 10 Men's Basketball Tournament.)
In addition, four other teams in the tournament era had unbeaten records, but did not play in any postseason tournament:
- 1940 Seton Hall Pirates (19–0) — not invited to either the NCAA Tournament or NIT.
- 1944 Army Cadets (15–0) — not invited to either the NCAA Tournament or NIT. (Given that this season was during World War II, it is also possible that Army chose to turn down tournament invitations.)
- 1954 Kentucky Wildcats (25–0) — declined a bid to the NCAA Tournament due to an NCAA ruling that graduate students could not compete.
- 1973 NC State Wolfpack (27–0) — ineligible for postseason competition due to rule violations earlier that season.
In the women’s game, the following national championship teams have had perfect records since the AIAW began sponsoring a championship tournament in 1972 (which was followed by the NCAA tournament in 1982):
- 1973 Immaculata Mighty Macs (20–0)
- 1975 Delta State Lady Statesmen (28–0)
- 1981 Louisiana Tech Lady Techsters (34–0)
- 1986 Texas Longhorns (34–0)
- 1995 Connecticut Huskies (35–0)
- 1998 Tennessee Lady Vols (39–0)
- 2002 Connecticut Huskies (39–0)
- 2009 Connecticut Huskies (39–0)
- 2010 Connecticut Huskies (39–0)
- 2012 Baylor Lady Bears (40–0)
The following teams have completed perfect regular seasons, but lost in the NCAA Tournament or other postseason action:
- The 1983 Oral Roberts Lady Titans (now nicknamed Golden Eagles) finished the regular season 24–0, but were not invited to the NCAA Tournament. They played in the National Women's Invitational Tournament, losing to Memphis State (now known as Memphis) in the second round. After winning a consolation game against Weber State, they finished the season 26–1.
- The 1990 Louisiana Tech Lady Techsters entered the NCAA Tournament at 28–0, but lost in the Final Four to Auburn to finish 32–1.
- The Vermont Catamounts were unbeaten entering the NCAA Tournament in both 1992 (29–0) and 1993 (28–0). They lost in the first round to George Washington in 1992 and Rutgers in 1993.
- The 1997 Connecticut Huskies entered the NCAA Tournament at 30–0, but lost in the final of the Midwest Regional to eventual national champion Tennessee, finishing 33–1.
- The 1998 Liberty Lady Flames entered the NCAA Tournament 28–0, but were seeded #16 in the Mideast Region and matched against Tennessee, with the Lady Vols crushing the Lady Flames 102–58.
- The 2003 Connecticut Huskies finished the regular season at 29–0, but lost to Villanova in the final of the Big East Tournament, ending their then-record winning streak at 70 games. The Huskies went on to win the NCAA Tournament, finishing 37–1.
- The 2007 Duke Blue Devils finished the regular season at 29–0, but lost in the semifinals of the ACC Tournament to North Carolina State. In the NCAA Tournament, they lost in the semifinals of the Greensboro Regional to Rutgers to finish 32–2.
- The 2010 Nebraska Cornhuskers finished the regular season at 29–0, but lost in the semifinals of the Big 12 Tournament to Texas A&M. In the NCAA Tournament, they lost in the semifinals of the Kansas City Regional to Kentucky to finish 32–2.
NCAA ice hockey
The most recent unbeaten season in NCAA ice hockey, and the first ever in today's Division I, was in 2012–13 by the Minnesota Golden Gophers, who became the first NCAA women's team ever to finish unbeaten (41–0–0).
The last men's team to finish unbeaten, and the last college team to do so before the 2012–13 Minnesota women, was the 1983–84 Bemidji State Beavers, who were then competing in Division II, a level of competition that no longer conducts a championship. Among schools in the top level of men's ice hockey, the last unbeaten season was by the Cornell Big Red in 1969–70, who went 29–0–0 in the University Division (the predecessor to today's Division I).
The 1955–56 Clarkson Golden Knights were undefeated (23–0–0), and Coach Bill Harrison won the NCAA Coach of the Year award, but Clarkson skipped the NCAA tournament because Clarkson had seniors with (4) years of college play which was against NCAA rules at the time. The 1969-1970 Cornell men's hockey team was also undeafeted with a 29-0 record.
Australian Football League (VFL/AFL)
The Australian Football League began in 1897 as the Victorian Football League, based entirely in the state of Victoria, before it expanded through the 1980s and 1990s to become the top level national league in the sport of Australian rules football. The length of a complete season (including finals matches) has typically been between 18 and 26 games. Throughout the history of the league, no team has ever completed a perfect season, although one team, Collingwood in 1929, has completed a perfect home-and-away season, finishing with a record of 18-0. The club went on to win the premiership, but did not complete a perfect season after losing the second semi-final against Richmond. Essendon in 2000 began the season 20-0 before losing to the Western Bulldogs, and St Kilda in 2009 began 19-0 before losing to Essendon; they were beaten by Geelong in the Grand Final.
South Australian National Football League
The SANFL has existed since 1877 within South Australia, and until the latter part of the twentieth century was of equivalent standard to the VFL. The only perfect season to be completed was by the 1914 Port Adelaide team, known as the “Invincibles”. Port finished the minor round with a 12–0 record, before winning both finals to finish with a 14–0 record and a perfect season. They also won the Championship of Australia against VFL premiers Carlton, to extend that record to 15-0. The closest any team got to Port Adelaide was North Adelaide, losing by 21 points in Round 10.
West Australian Football League
The WAFL has existed since 1885 within Western Australia, and until the latter part of the 20th century was of equivalent standard to either the VFL or SANFL. The 1946 East Fremantle team is the only club in senior WAFL football to have managed a perfect season or even a perfect home-and-away season, winning all twenty-one of its games; it is noted that the playing lists of many of its opponents had been seriously depleted by World War II.
Victorian Football League (VFA/VFL)
The Victorian Football League, known until 1996 as the Victorian Football Association, began in 1877 and was Victoria’s premier football league until 1897, and has been the second-tier league in the state since. Perfect seasons have been completed on four occasions in VFA/VFL history:
- by North Melbourne in 1915, with a record of 14-0
- by North Melbourne after an abeyance due to World War I in 1918 with a record of 12-0; in the process they won an Australian record 49 straight games and played 58 games without loss in all
- by Geelong West in 1972 Division 2, with a record of 20-0
- by Port Melbourne in 2011, with a record of 21-0.
There were also cases of teams going undefeated through the season in the nineteenth century, but none completed perfect seasons because some of their matches were drawn.
Four other teams have completed perfect home-and-away seasons, but subsequently lost finals matches:
- North Melbourne in 1919 won all eighteen home-and-away games before losing to Brunswick in the second-semi-final and Footscray in the Grand Final.
- Coburg in 1927 won all eighteen home-and away games before drawing with Port Melbourne in the second semi and then losing by 59 points in the replay. The Lions recovered to beat Brighton by 34 points in the Grand Final.
- Coburg in 1945 won all twenty home-and-away games before losing by seventeen points to Williamstown in the second semi-final and being eliminated by two points to Port Melbourne in the preliminary final.
- Williamstown in 1957 won all twenty home-and-away games before losing narrowly to Moorabbin in the second semi final, and being thrashed by twelve goals by Port Melbourne in the preliminary final.
National Rugby League
The National Rugby League has existed since 1908, being originally known as the New South Wales Rugby League and before the Super League war of 1995 as the Australian Rugby League. In its history, only one team has completed a perfect season: the South Sydney Rabbitohs in 1925, who won all twelve games contested.
Five other teams have gone undefeated but featured at least one drawn match: Balmain (1915), North Sydney (1921), Eastern Suburbs (1936 and 1937) and St George (1959). Manly began the 1995 season with 15 wins, the most before suffering a loss or draw.
The New Zealand All Blacks were the first and currently only professional rugby team to produce a perfect rugby test season in 2013. They successfully defeated France four times, Australia three times, South Africa and Argentina twice and also beat Japan, England and Ireland in their incredible winning run. They produced a record of 14-0-0, defeating the top 5 ranked teams below them in the IRB world rankings.
The Southern Hemisphere’s principal team competition, Super Rugby, established as Super 12 in 1996 and later known as Super 14 before adopting its current name in 2011, has seen only one perfect season. The Crusaders, based in Christchurch and representing a large portion of the South Island of New Zealand, finished the 2002 Super 12 season with an 11–0–0 record and went on to win both of their finals matches to claim the season crown unbeaten.
One other team has won a championship unbeaten: in 1997, the Auckland Blues (known simply as “Blues” since 2000), which at the time represented the central and southern parts of the Auckland area plus some adjacent regions to the south, finished the regular season with one draw from 11 matches. They also won both of their finals matches to claim the title.
The Currie Cup is South Africa’s top tier provincial rugby union competition. During the 2012 Currie Cup First Division, the Eastern Province Kings, based in Port Elizabeth, and representing the western half of the Eastern Cape, finished the regular season with twelve wins and two draws from 14 matches. The team went on to win both the semi-final and final, to finish with a record of 14 wins and 2 draws from 16 matches.
English first-class county cricket has existed as the top tier of domestic cricket in England since the middle nineteenth century, and until the 1950s it was up to the highest standard of the game. Seasons have varied in length: before the 1880s, they were generally less than ten matches in length and some “first-class” counties played only against one or two different opponents, so that a team winning all its games was not implausible. Between 1887 and 1929, seasons were gradually increased in length to a standard twenty-eight matches for all counties. However, because of the development and popularity of one-day cricket, seasons have been reduced to twenty-four games in 1969 and twenty in 1972, though this was increased by two in 1977 and 1983. With an increase to four days for all games, sixteen or seventeen games have been played since 1993.
Also, because of improvements to pitches via the heavy roller and covering to protect from rain, the proportion of games “drawn” (not finished) has steadily risen since the 1870s.
Since tables of results have been kept in 1864, the only team to have competed a true perfect season - winning outright every game - was Yorkshire in 1867 when led by George Freeman’s and Tom Emmett’s deadly fast bowling on uncovered and unrolled pitches, they won all seven county games.
Since 1868 numerous county teams in longer schedules have finished a season unbeaten, but none have managed to win every single game outright:
|1864||Surrey||6||0||2||Also defeated a combined England team by eight wickets|
|1876||Gloucestershire||5||0||3||WG Grace scored over 1,000 runs in August including the first two triple centuries in first-class cricket|
|1877||Gloucestershire||7||0||1||Defeated England by five wickets|
|1881||Lancashire||10||0||3||One match against Middlesex cancelled because Harrow Wanderers booked Lord’s|
|1884||Nottinghamshire||9||0||1||Only draw against Surrey in August Bank Holiday game saw Surrey with three wickets in hand and 153 runs to win|
|1900||Yorkshire||16||0||12||Lost only two games, both at home to Somerset between 1900 and 1902.
Did lose to MCC at Lord’s with J.T. Hearne taking nine for 71 on a perfect pitch.
|1907||Nottinghamshire||15||0||4||One match abandoned against Yorkshire.
Hallam and Wass took 298 wickets between them in very wet summer
|1925||Yorkshire||21||0||11||Most games and most wins by unbeaten county team|
|1926||Yorkshire||14||0||17||Finished second, narrowly behind Lancashire who won seventeen games and lost two.
Played seventy-one games without loss before losing to Warwickshire on May 23, 1927
|1928||Lancashire||15||0||15||Went 35 games without loss and overall lost only once in eighty-three county games before losing to Sussex on May 24, 1929.|
|1928||Yorkshire||8||0||20||Finished fourth of seventeen teams
Played fifty-six unbeaten county matches before losing to Kent on 1 July 1929, but only won fourteen of these
|1930||Lancashire||10||0||18||Had lost only four of last 135 games at end of season.|
|1974||Lancashire||5||0||15||Finished only eighth of seventeen teams
Lowest win percentage by unbeaten county team
|1998||Leicestershire||11||0||6||Lost only two games between 1996 and 1998|
|1999||Surrey||12||0||5||Last season of single-division Championship|
|2012||Yorkshire||5||0||11||Finished second in Second Division|
The ANZ Championship, the principal netball competition for Australia and New Zealand was established in 2008 to replace the Commonwealth Bank Trophy. Comprising ten teams (five from Australia and five from New Zealand) there has so far been one perfect season, by the Mission Queensland Firebirds, based in Brisbane, Queensland in 2011. The Firebirds won thirteen regular season games and both their finals matches for a record of 15-0.
Many association football teams have also had perfect seasons, however doing so in a season of 20 or more matches is very rare. Clubs to have achieved this include: Dresdner SC of Germany in 1942–43 (23 wins out of 23), Ferencvárosi of Hungary in 1931–32 (22), Sunrise Flacq United of Mauritius in 1995–96 (22), and Nacional of Uruguay in 1941 (20). Al-Ahly (of Egypt) hold the record of going a whole season being unbeaten, in all possible competitions they were involved in (46 matches in total played in: Egyptian Premier League, Egyptian Cup, Egyptian Super Cup and CAF Champions League). The longest winning streak of any team over multiple seasons was Sparta Prague’s run of at least 51 wins in a row, between 1920 and 1923.
Teams finishing a season unbeaten (i.e. having won or drawn every match) are more common. Arsenal in the 2003–04 English Premier League season, finished with no losses from 38 games 100 years after Preston North End unbeaten streak in 22 league games and all of its FA Cup games in 1888-89. At the same time, AFC Wimbledon finished with a record of 42 wins, 4 draws and 0 defeats out of 46 games in their Combined Counties League Premier Division season. In Italy, Perugia (1978–79), A.C. Milan (1991–92), and Juventus F.C. (2011–12) have been undefeated. In Turkish soccer, Galatasaray in 1985-86 season uniquely completed the season unbeaten but finished as runners-up. Beşiktaş J.K. in 1991–92 completed the season unbeaten and became Turkish League’s only ever champions without defeat. In Portugal, Benfica (1972–73) was the first club to do so and won 28 matches – 23 consecutively – out of 30, and drew two. They also went undefeated in 1977–78 but finished second to one-loss Porto. Porto finished the 2010–11 and 2012–13 seasons unbeaten, with a respective win–draw record of 27–3 and 24–6. In Saudi Arabia, Al-Hilal FC finished a 26-game season in the 2010–11 with 19 wins and 7 draws. Greek club Panathinaikos F.C. finished the 1963-64 season, Hungarian club Debreceni VSC finished the 2011-12 season, Norwegian club Rosenborg BK finished the 2010 season undefeated. The only unbeaten champion in Brazil was SC Internacional, who won the 1979 season with 16 victories and 7 ties.
FIFA World Cup
The likelihood of a national team in the FIFA World Cup to win all of its group stage matches, as well as every knockout game, to become the champion is higher than most domestic teams, given this unofficial “season” has a maximum length of only seven games. This is not counting the qualifying round of the tournament, which lasts over a year and has had a varied format since 1934. Only one team, the 1970 World Cup champion Brazilian team has won every game in all both qualification and finals, without being the host country or defending champions (which allows a team to skip qualifying rounds), in this case, a total of 13 games. In 2010 the Dutch team came very close achieving the same feat as the Brazilian team did in 1970. The Netherlands won 8 out of 8 qualifying games and went on to win the next 6 World Cup matches only to lose to Spain in the final, ending with a 14–0–1 record.
The 1990 West German team was the last to be a champion while incurring no losses in all rounds; they had 8 wins and 5 ties. The last team to win with no losses or ties in the last two rounds (group round and knockout round) was the Brazilian team at the 2002 World Cup.
FIFA Women’s World Cup
Through 2011, the likelihood of a national team winning all of its matches in the FIFA Women's World Cup has been slightly greater than in the men's version. The Women's World Cup began in 1991 with 12 teams, and expanded to 16 effective in 1999. Under both structures, the winning team has only had to win six games (three in group play and three in the knockout stage) to win the title unbeaten. The tournament will expand to 24 teams in 2015, at which time the number of games that the champion must play will increase to seven.
The 2011 event, won by Japan, was the first in which the champion lost in group play; the other finalist, the USA, had also lost in group play. Each previous team to have won the title — the USA in 1991 and 1999, Norway in 1995, and Germany in 2003 and 2007 — won all of its group stage matches. In fact, only one of these teams, the USA in 1999, had a knockout match go to extra time—specifically the final against China, which ultimately went to a penalty shootout. Germany won all of its matches in the 2007 final tournament without giving up a goal, becoming the first team in either the men's or women's World Cup to accomplish this feat.
Three Women's World Cup champions also went through their qualifying stage without a loss or draw:
Of the other two teams to win the Women's World Cup without a loss or draw in the finals:
- Norway went through their 1995 qualification campaign with 8 wins, 1 draw and 1 loss.
- The USA automatically qualified for the 1999 edition as host.
In 2011/2012, German handball champion THW Kiel achieved a perfect season of as many as 34 matches. Additionally, the team also won the national DHB Cup and the international EHF Champions League.
In 2011 and 2012, the Washington Kastles of World Team Tennis completed back-to-back perfect seasons, the first major sports franchise in the United States to do so. The Kastles swept each of the 2011 and 2012 regular seasons with a perfect 14-0 record, then in each season went on to win their two postseason games and league’s championship, amassing a 32 game wining streak in the process. This streak stands one short of the all-time professional sports record in the United States by the 1971-72 Los Angeles Lakers.
In the 2012-2013 Season, Vakıfbank İstanbul won all 47 games, and reached the championship trophies in Turkish Women's Volleyball League, 2012-2013 Turkish Women's Volleyball Cup and 2012–13 CEV Women's Champions League.
Vakıfbank İstanbul won 6 games in Turkish Women's Volleyball Cup, 12 games in CEV Women's Champions League, and 29 games (22 normal season, 7 play-offs) in Turkish Women's Volleyball League, and never lost in the 2012-13 Season.
As of December 9, 2013, Vakıfbank İstanbul have reached a 66-game winning streak.
They started the 2013-2014 Season with a win in the Turkish Super Cup on October 2, 2013. They also reached 2013 FIVB Women's Club World Championship title winning all four games between October 10 and October 13, 2013. Having started Turkish Women's Volleyball League's 2013-14 Season with ten wins and 2013–14 CEV Women's Champions League with four wins, they extended their winning streak to 66 games. 
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