Number (sports)

Squad number, as depicted on an association football jersey.

In team sports, the number, often referred to as the uniform number, squad number, jersey number, shirt number, sweater number, or similar (with such naming differences varying by sport and region) is the number worn on a player's uniform, to identify and distinguish each player (and sometimes others, such as coaches and officials) from others wearing the same or similar uniforms. The number is typically displayed on the rear of the jersey, often accompanied by the surname. Sometimes it is also displayed on the front and/or sleeves, or on the player's shorts or headgear. It is used to identify the player to officials, other players, official scorers, and spectators; in some sports, it is also indicative of the player's position.

The International Federation of Football History and Statistics, an organization of association football historians, traces the origin of numbers to a 1911 Australian rules football match in Sydney, although photographic evidence exists of numbers being used in Australia as early as May 1903. Player numbers were used in a Queensland vs. New Zealand rugby match played on 17 July 1897, in Brisbane, Australia, as reported in the Brisbane Courier.

Association football

Main article: Squad number (association football)

In association football, numbers were traditionally assigned based on a player's position or reputation on the field, with the starting 11 players wearing 1–11, and the substitutes wearing higher numbers. The goalkeeper would generally wear number 1, then defenders, midfield players and forwards in ascending order.

Numbers being assigned to each player in a squad was initiated for the 1954 World Cup, where each man in a country's 22-man squad wore a specific number for the duration of the tournament. In 1993, England's Football Association switched to persistent squad numbers, abandoning the mandatory use of 1–11 for the starting line-up. It became standard in the FA Premier League in the 1993–94 season, with names printed above the numbers. Most European top leagues adopted the system over the next five years.

It is common for players to change numbers within a club as their career progresses. For example, Cesc Fàbregas was first assigned the number 57 on arrival at Arsenal in 2003. On promotion to the first team squad he was switched to number 15 before inheriting his preferred number 4 following the departure of Patrick Vieira.

Very high numbers, the most common being 88, are often reserved and used as a placeholder, when a new player has been signed and played by the manager prior to having a formal squad number. However, in some countries these high numbers are well used, in some cases because the players preferred number is already taken or for other reasons. On joining A.C. Milan; Andriy Shevchenko, Ronaldinho and Mathieu Flamini all wore numbers reflecting the year of their birth (76, 80 & 84 respectively), because their preferred numbers were already being worn.

Australian rules football

In Australian rules football, players traditionally wear numbers on the backs of their guernseys, although some competitions (the WAFL is one example) may feature teams who wear smaller numbers on the front, usually on one side of the chest. The number being worn is usually not relevant to the player's position on the ground, although occasionally a club will allocate the Number 1 guernsey or an otherwise prestigious number to the team captain (such as the Richmond football club, which allocates Number 17 to its team captain in honor of Jack Dyer, who wore that number with distinction). Port Adelaide assigns Number 1 to the team captain. In these situations, it is usually customary for players who relinquish the captaincy to switch to another.

AFL clubs generally do not retire numbers (although Geelong temporarily retired the Number 5 between 1998 and 2005 after the retirement of Gary Ablett Sr.), but instead will often choose to give their more prestigious numbers to highly touted draftees or young up-and-coming players who are shown to have promise and may share certain traits with the previous wearer, such as position or playing style. For example, as of 2010, Michael Hurley inherited the Number 18 jumper left vacant by the retired Matthew Lloyd, effectively keeping the No. 18 guernsey in Essendon's goal-square for another era.

Sons of famous players will often take on their father's number, especially if they play at the same club. Sergio Silvagni and his son Stephen, for example, both wore Number 1 for Carlton. Matthew Scarlett wears his father John's Number 30 at Geelong. In contrast, some sons of famous players also prefer to take on other numbers in the hopes that it will reduce the burden of having to fulfill high expectations. Notable examples of this are Gary Ablett Jr. at Geelong (who wore Number 29 instead of his father's Number 5) and Jobe Watson at Essendon, who passed up Tim's Number 32 in favour of Number 4.

Clubs will often feature retiring champions "passing on" their famous guernsey numbers to the chosen successors, usually in ceremonial fashion, such as a club function or press conference.

The highest number worn in a VFL/AFL game is number 65 by Andrew Witts of Collingwood for seven games in 1985. With the demise of Reserves and Under 19's teams it is highly unlikely that any player will play senior football in a number as high again. The highest number used in the 2011 season was number 55 for Nathan Ablett in two games for the Gold Coast Suns.

American football

Main article: Uniform number (American football)

NFL

A system of assignment of jersey numbers was initiated in American football's NFL in 1952; it was updated and made more rigid in 1973, and has been modified slightly since then. Numbers are always worn on the front and back of a player's jersey, and so-called "TV numbers" are worn on the sleeve or shoulder. The Cincinnati Bengals were the last NFL team to wear jerseys without TV numbers on a regular basis in 1980, though since then several NFL teams have worn throwback uniforms without them, as their jersey designs predated the introduction of TV numbers. Players' last names, however, are required on all uniforms, even throwbacks which predate the last name rule. Since 2008, TV numbers have not been mandatory under NFL rules.

Some uniforms also feature numbers either on the front, back, or sides of the helmet (in pro football, these were most prominently worn on the San Diego Chargers "powder-blue" uniforms). Players have often asked the NFL for an exception to the numbering rule. In 2006, for example, New Orleans Saints running back Reggie Bush requested to keep the number 5 he wore in college. His request was declined, and he was assigned number 25 by the team.

Below is the numbering system established by the NFL. It has been primarily unchanged since 1973, though small changes have been made on occasion since then, most recently opening up the 10-19 range for wide receivers in 2004, and opening 40-49 up to linebackers in 2015, with the latter decree being named the "Brian Bosworth rule", who wanted to wear 44, but was ordered to change it to 55. In the same year, numbers 50-59 are open to defensive linemen, the first benefactor is Jerry Hughes.

• 1–9: quarterbacks, kickers, and punters.
• 10–19: quarterbacks, kickers, punters, and wide receivers
• 20–39: running backs and defensive backs
• 40–49: running backs, defensive backs, linebackers, and tight ends.
• 50–59: linebackers and centers, defensive linemen (from 2015)
• 60–79: offensive linemen and defensive linemen.
• 80–89: wide receivers and tight ends.
• 90–99: linebackers and defensive linemen.

Numbers 0 and 00 are no longer allowed, but they were issued in the NFL before the number standardization in 1973. George Plimpton wore 0 during a brief preseason stint at quarterback for the Detroit Lions. Jim Otto ("aught-oh") wore number "00" during most of his career with the Oakland Raiders. Wide receiver Ken Burrough of the Houston Oilers also wore "00" during his NFL career in the 1970s.

This NFL numbering system is based on a player's primary position. Any player wearing any number may play at any position at any time (though players wearing numbers 50–79 or 90-99 must let the referee know that they are playing out of position by reporting as an "ineligible number in an eligible position"). It is not uncommon for running backs to line up at wide receiver on certain plays, or to have a lineman or linebacker play at fullback or tight end in short yardage situations. In preseason games, when teams have expanded rosters, players may wear numbers that are outside of the above rules. When the final 53-player roster is established, they are reissued numbers within the above guidelines.

College and high school

In college football and high school football, a less rigid numbering system is employed. The only rule is that members of the offensive line (centers, guards, and tackles) that play in ineligible positions (those that may not receive forward passes) must wear numbers between 50 and 79. Informally, certain conventions still hold, and players often wear numbers in the ranges similar to their NFL counterparts; though the lowest numbers are often the highest prestige, and thus are often worn by players at any position. Kickers and punters are frequently numbered in the 40's or 90's, which are the least in-demand numbers on a college roster. The increased flexibility in numbering of NCAA rosters is needed since NCAA rules allow 85-player rosters; thus teams would frequently exhaust the available numbers for a position under the NFL rules.

One oddity of college football is that the same squad number can be shared by two (or more) players, e.g., an offensive and a defensive player. Usually one of the players is a reserve who rarely plays but there are exceptions: In the 2009 and 2010 seasons, that same number (5) was worn by South Carolina starting quarterback Stephen Garcia and starting cornerback Stephon Gilmore. Gilmore was also used as a wildcat quarterback in games against Clemson in 2009 and Southern Miss in 2010. The player change, since both players wore the same number, caused some confusion among opposing defenses, but was legal, since both players were not on the field at the same time. In 2012, the No. 5 was worn by two Notre Dame starters—quarterback Everett Golson and linebacker Manti Te'o.

Baseball

Main article: Uniform number (Major League Baseball)

In baseball, players generally wear large numbers on the back of their jersey. Some jerseys may also feature smaller numerals in other location, such as on the sleeves, pants, or front of the shirt. The purpose of numerals in baseball is to allow for easy identification of players. Some players have been so associated with specific numbers that their jersey number has been officially "retired". The first team to retire a number was the New York Yankees, who retired Lou Gehrig's #4 in 1939.

In the early years of baseball, teams did not wear uniform numbers. Teams experimented with uniform numbers during the first two decades of the 20th century, with the first Major League team to use them being the 1916 Cleveland Indians which used them for a few weeks before abandoning the experiment. Again in 1923, the St. Louis Cardinals tried out uniforms with small numbers on the sleeves, but the players did not like them, and they were removed. For the 1929 Major League Baseball season both the New York Yankees and Cleveland Indians put numbers on their jerseys, the first two teams to do so, beginning a trend that was completed by 1937, when the Philadelphia Athletics became the last team to permanently add numbers to their jerseys.

There is no system for numbering players in baseball, though in the very early years some teams did employ their own systems. The 1929 New York Yankees handed out uniform numbers based on a player's position in the batting order; which is why Babe Ruth and Lou Gehrig wore their famous numbers 3 and 4; they batted third and fourth respectively that season. Numbers 1–8 were assigned to the regular starters at their respective batting order positions, numbers 9 and 10 were assigned to the Yankees two backup catchers, while pitchers and backup fielders were assigned higher numbers. Today there is no rhyme or reason to a player's uniform number, players may pick their own number for personal reasons, or accept a number assigned by the team.

Canadian football

Canadian football follows the same general rules as American football, with some minor exceptions. In the original numbering system, offensive linemen wore numbers from 40–69 and numbers 70–79 were allocated to receivers. A rules change in 2008 switched numbers 40–49 from offensive linemen to eligible receivers. Any eligible player, whether he is a quarterback, running back, receiver, or a kicker, can wear any eligible number. Doug Flutie wore his Boston College number of 22 when he played quarterback for the BC Lions and No. 20 for the Calgary Stampeders. Currently, numbers 1–49 and 70–89 are eligible while 50–69 are not. Numbers 90–99 are generally worn on defense although in the early days of the Canadian Football League, 90s were common on offense. The number 0 is also allowed in the CFL. A defensive player can wear any number he chooses, regardless of the position he plays.

Rugby league

Further information: Rugby league positions

In rugby league each of the thirteen positions on the field traditionally has an assigned shirt number, for example fullback is "1". In recent times squad numbering has been used for marketing purposes in the Super League competition. In Super League each player is given a squad number for the whole season, the first choice starting line-up at the beginning of the season will usually be given shirts 1–13 but as interchanges (substitutions) occur during the game and injuries etcetera occur during the season, it is less likely that the number a player wears will match the position they are playing.

Furthermore, a growing number of teams in both Australia and England (such as South Sydney Rabbitohs and Warrington), as well as most major representative teams, have adopted the cricket custom of "club numbers", in which each player is given a unique number in the order of when he made his first senior appearance for a specific side. These numbers are typically small and embroidered above or below the club crest on a player's shirt.

Rugby union

Further information: Rugby union numbering schemes and Rugby union positions

When included in the starting line-up, a player's rugby shirt number usually determines their position. Numbers 1–8 are the 'forwards', and 9–15 the 'backs'. Rugby union even has a position named simply after the shirt normally worn by that player in the "Number 8" position. Several clubs (Leicester and Bristol particularly) used letters instead of numbers on shirts, although have now fallen into line with the rest of the clubs.

• 1-Loosehead Prop
• 2-Hooker
• 3-Tighthead Prop
• 4-Lock/Second Row
• 5-Lock/Second Row
• 6-Blindside Flanker (Openside in South Africa)
• 7-Openside Flanker (Blindside in South Africa)
• 8-Number 8
• 9-Scrum Half
• 10-Fly Half
• 11-Left Winger
• 12-Inside Centre
• 13-Outside Centre
• 14-Right Winger
• 15-Full Back

Gaelic Games

Main article: Gaelic football, hurling and camogie positions

In Gaelic football, hurling and camogie, the goal keeper generally wears the number 1 shirt, and the rest of the starting team wears numbers 2–15, increasing from right to left and from defence to attack: substitutes' numbers start from 16.

Cricket

The 1995–96 World Series Cup in Australia saw the first use of shirt numbers in international cricket, with most players assigned their number and some players getting to choose their number, most notably Shane Warne wearing 23 as it was his number when he played junior Aussie Rules for St Kilda Football Club. Other countries soon adopted the practice, although players would typically have different numbers for each tournament, and it was several years later that players would consistently wear the same number year-round. Ricky Ponting (14) still uses the same number as in that initial season.

Player numbering was first used in the Cricket World Cup in 1999, where the captains wore the number 1 jersey and the rest of the squad was numbered between 2 and 15. An exception was that South African captain Hansie Cronje retained his usual number 5 with opener Gary Kirsten wearing the number 1 which he had also done previously.

Shirt numbers no longer remain exclusive to the short forms of the game, and navy blue numbers are now used on the playing whites in the Sheffield Shield to aid spectators in distinguishing players. However, a recent fashion that has been taken up by several nations is the process of giving a player making his Test debut an appearance number, along with his Test cap, for reasons of historical continuity. The number is in the order a player makes his Test debut. If two or more players make their debut in the same match, they are given numbers alphabetically based on surname. For example, Thomas Armitage is Test player Number 1 for England. He made his debut in the very first Test Match, against Australia, on 15 March 1877, and was first in alphabetical order amongst that England XI. Adam Lyth and Mark Wood are the most recent test debutants for England, making their debut on 21 May 2015 against New Zealand. Lyth is Test player Number 666 for England, and Wood is Number 667 (as they debuted in the same match, Lyth has the lower number by virtue of being alphabetically before Wood). These numbers can be found on a player's Test uniform, but it is always in discreet small type on the front, and never displayed prominently.

Basketball

American basketball leagues at all levels traditionally use single and double digits between 0 and 5 (i.e. 0, 00, 1–5, 10–15, 20–25, 30–35, 40–45, and 50–55). The NCAA and most amateur competitions mandate that only these numbers be used. This eases non-verbal communication between referees, who use fingers to denote a player's number, and the official scorer. In college basketball, single-digit players' numbers are officially recorded as having a leading zero. Teams can have either a "0" or "00", but they cannot have both. Mathematically, these numbers can be considered as senary rather than decimal numbers, since the senary number system uses the same six digits.

The rule about "0" and "00" also applies to the NBA. In 2000, Utah Jazz center Greg Ostertag changed from "00" to "39" so Olden Polynice could wear No. 0 and in 2003, Washington Wizards center Brendan Haywood switched from No. 00 to No. 33 so Gilbert Arenas (who had the nickname "Agent Zero" already at this point) could wear #0.

The National Basketball Association has always allowed other numbers between 0 and 99, but use of digits 6 through 9 is less common than 0 through 5 since most players tend to keep the numbers that they had previously worn in college. However, with the increase in the number of international players, and other players who have been on national (FIBA) teams who change NBA teams and cannot keep their number with the previous team because another player has worn it or is retired, players have adopted such higher numbers (Patrick Ewing with No. 6 in Orlando). When Michael Jordan retired in 1993, the Chicago Bulls retired his 23; when he came out of retirement he chose to wear 45 until, during the 1995 NBA post-season, he went back to his familiar 23. Also, players cannot change numbers midseason, but they used to be able to (Andre Iguodala and Antoine Wright changed from No. 4 and No. 15 to No. 9 and No. 21 for Chris Webber and Vince Carter, respectively). Since Kelenna Azubuike was inactive all season, Carmelo Anthony was able to wear Azubuike's No. 7 when traded to the Knicks in 2011, but since Rodney Stuckey was active, Allen Iverson could not wear No. 3 when traded to the Pistons in 2009. (Anthony would not have been able to wear his normal No. 15 anyway and would have had to trade jerseys; the Knicks have retired the jersey number.)

Up to 2014, players in FIBA-organized competitions for national teams, including the Olympic Games, World Cup and Women's World Championship, had to wear numbers from 4 to 15. Under FIBA rules, national federations could also allow any numbers with a maximum of 2 digits for their own competitions; this rule also applied in transnational club competitions, most notably the Euroleague. At present, players are allowed any numbers from 1 to 99, additionally 0 and 00.

Ice hockey

Ice hockey does not have any formalized uniform numbering rules. Historically, in the National Hockey League, starting goaltenders wore number 1, the backup goalie wore number 30, and the other players (the "skaters") wore low numbers (generally numbers 2 through 29). It is still traditional for goaltenders to wear either number 1 or numbers near 30 (in a range from approximately number 29 to number 41). After the NHL lockout in 2004-05, it became more common for goalies to wear even numbers in the 30s; previously, the overwhelming majority of goaltenders would wear odd numbers in the 30s. Some well-known goalies with non-traditional numbers include José Théodore (number 60), Kevin Weekes (number 80), Sergei Bobrovsky (number 72), Tomáš Vokoun (number 92), Braden Holtby (number 70), Corey Crawford (number 50), Andrei Vasilevskiy (number 88), and Ron Hextall (number 27; number 72 when number 27 was unavailable). Evgeni Nabokov and Ed Belfour have both worn number 20 in honor of their mentor (and in Belfour's case, a position coach at one time in his career), legendary Russian goalie Vladislav Tretiak. Tretiak wore number 20 because in the Soviet Union it was a tradition that the starting goalie wore number 1, skaters wore numbers 2–19 and the back-up goalie wore 20.

In recent years, it has become more common for players to wear numbers in the 30s and above. This is due in part to many teams having retired lower numbers. The two oldest NHL teams still playing in the league — the 1909-founded Montreal Canadiens, for example, have only two single-digit numbers left un-retired (6 and 8), and the Canadiens' greatest rival, the 1924-founded Boston Bruins also have only two single-digit numbers left un-retired (1 and 6).

Many players have worn higher numbers up through number 99 (though number 99 itself is now retired league-wide in the NHL to honor Wayne Gretzky). For example, Jaromír Jágr has worn number 68 through his entire playing career from juniors onward in honor of the year of the Prague Spring and his grandfather's death; Alexander Mogilny wore number 89 to honor the year he defected to the United States from the Soviet Union; Sidney Crosby wears number 87 because his birth date is 7 August 1987, written "8/7/87" in the U.S. date format; Patrick Kane of the Chicago Blackhawks wears number 88 because of his birth year, 1988; Wojtek Wolski chose 86, representing his birth year of 1986, when he joined the Phoenix Coyotes, as the number 8 he wore with Colorado wasn't available; and Cory Conacher has worn 88 and 89 in honor of Kane (his personal friend) and Mogilny. In the 1990s, many players chose their numbers in honor of the year they were drafted, such as Sergei Berezin, wore number 94 because he was drafted in 1994.

Doubling of a single-digit number has occasionally been used for players whose numbers were unavailable. For example, Phil Esposito switched to number 77 when he joined the New York Rangers where number 7 was worn by Rod Gilbert; and Ray Bourque, who succeeded Esposito in wearing number 7 for the Boston Bruins, switched to number 77 — itself retired on 4 October 2001 by the Bruins to honor Bourque — to allow the Bruins to retire Esposito's original number 7 on 3 December 1987. That same season, Paul Coffey switched to number 77 when he was traded from Edmonton to Pittsburgh. In addition, Gretzky wore number 99 because number 9, which he wore in tribute to Gordie Howe, was taken on his junior team. Similarly, Mario Lemieux wore number 66 (99 upside down) as a tribute to Gretzky. Going the other way, Todd Bertuzzi, who wore number 44 for many years, switched to number 4 when he was traded to the Anaheim Ducks in 2007, since number 44 was already in use by alternate captain Rob Niedermayer. Jordin Tootoo wears number 22, as the numbers "two two" are pronounced the same as his last name. In a similar vein, Mike Commodore considered wearing number 64, a reference to the famed Commodore 64 computer when he was acquired by Detroit, but ended up returning to the more traditional 22, while Steve Heinze wore number 57, referencing the '57 varieties' advertising campaign of Heinz for the latter part of his career (he was initially denied doing so by the Bruins). Sometimes numbers are even reversed. Scott Gomez wore the number 19 when he played for the Rangers (he wore 23 during his tenure with the NJ Devils) until he joined the Montreal Canadiens, who had retired that number in honor of Larry Robinson. Instead of changing to a completely different number, he chose 91 and switched to 11 for the 2010–11 season.

Some players wearing a two-digit number may replace the number 1 with the number 7, or vice versa, if the number is unavailable. For example, Theoren Fleury, who wore number 14 for most of his career, wore number 74 for team Canada at the 2002 Winter Olympics. In the 2013-2014 season, the Red Wings assigned number 11 to newly signed free agent Daniel Alfredsson (his number when he played for the Ottawa Senators) as it became available when Daniel Cleary signed a free agent contract with the Philadelphia Flyers. However, when Cleary changed his mind and returned to the Red Wings, the league prohibited Alfredsson from switching to number 24 and returning 11 to Cleary due to marketing efforts already under way for the 2014 Winter Classic game. Cleary chose number 71 instead.

Number 84 was the final number to have never been worn in the NHL, until Canadiens forward Guillaume Latendresse first wore the number on 29 September 2006, although he has reversed the number (48) since joining the Minnesota Wild. The least-used number is 98, worn only by Brian Lawton of the Minnesota North Stars in the 1983-84 and 1984-85 seasons. The second least-used number is 69, worn for two games in 2003–04 by Mel Angelstad of the Washington Capitals and was once used by Andrew Desjardins of the San Jose Sharks before he switched to number 10. The last player to wear a form of zero in the NHL was Martin Biron, who wore number 00 with the Buffalo Sabres in three games in 1995–96. By the time he returned to the Sabres in 1998, the number zero, single digit or double digit, was not allowed anymore, forcing him to wear number 43 (which he wore for the rest of his career). This was because of a glitch in the NHL's new stat-tracking software that limited player numbers to the range of 1 to 99. Only three other NHL players have worn number 0 or 00: Paul Bibeault (0), John Davidson (00), and Neil Sheehy (0). Other than Davidson's and Biron's 00, no player has worn a leading zero as part of his uniform number.

Auto racing

In most auto racing leagues, cars are assigned numbers. The configuration of stock cars, however, makes the numbers much more prominent. (Aerodynamic open-wheel cars don't have nearly the amount of flat surface that a stock car has.) Numbers are often synonymous with the drivers that carry them. Dale Earnhardt, Sr. is associated with the number 3 (although that number is actually associated more with its owner, Richard Childress, who has taken the number out of reserve for his grandson Austin Dillon, first in the Camping World Truck Series, then in the Nationwide Series, and finally in the Sprint Cup Series beginning in 2014), while Richard Petty is associated with Number 43, Wood Brothers Racing with Number 21, and Jeff Gordon to the Number 24.

NASCAR

In NASCAR, numbers are assigned to owners and not specific drivers. Drivers that spend a long time on a single race team often keep their numbers as long as they drive for the same owners. When drivers change teams, however, they take a new number that is owned by that team. Jeff Burton, for example, raced for 3 different teams between 1994 and 2013, and had 4 different numbers in that time. In 1994 and 1995 he raced the Number 8 car, then owned by the Stavola Brothers. From 1996 to mid-2004 he raced for Roush Racing, and drove the Number 99 car. After leaving Roush Racing for Richard Childress Racing, he changed to car Number 30 (for the rest of the 2004 season) and drove Number 31 (also an RCR car) from 2005 to 2013. The Number 99 car he used to drive for Roush was driven by Carl Edwards from 2004 to 2014. When Dale Earnhardt, Jr., having raced under No. 8 at Cup-level moved from DEI to Hendrick Motorsports he attempted to take the number with him. When that failed Hendrick was able to secure the No. 88 from Robert Yates Racing.

Formula One

Formula One car numbers started to be permanently allocated for the whole season in 1974. Prior to this numbers were allocated on a race-by-race basis by individual organisers. From 1974 to the mid-1990s, the numbers 1 and 2 would be allocated to the reigning world champion and his teammate, swapping with the previous year's champions. Once numbers had been allocated, teams retained the same numbers from year to year, only exchanging for 1 and 2 when the drivers' World Championship was won. As a result, Ferrari are infamous for having carried 27 and 28 for many years (every season from 1980 to 1989, and then again from 1991 to 1995), these numbers having originally been allocated to new entrant Williams in 1977 and passed to Ferrari when Alan Jones replaced Jody Scheckter as World Champion after the 1980 season. Numbers were reallocated occasionally as teams departed and joined the series, but this scheme persisted until the late 1990s; one team, Tyrrell, kept the same numbers (3 and 4) throughout this period for every season between 1974 and 1995.

The system was changed again in 1996. From that point through 2013, numbers were assigned annually, first to the reigning World Champion driver (who received number 1) and then his team-mate (who received number 2); after that the numbers were assigned to constructors sequentially according to their position in the previous season's Constructors' Championship, so that numbers were allocated (if the reigning champion is not driving for the reigning constructor's champion team) from 3 and 4, 5 and 6, and so on (skipping 13 with the seventh-placed team using 14 and 15). The only stipulation was that the World Drivers' Champion was entitled to the number 1 car regardless of the constructor's results; this was relevant when the winning driver's team failed to win the Constructors Championship, or if the winning driver changed teams after winning the championship—for example, when Damon Hill moved to the Arrows team for the 1997 season. This situation happened again in 2007 when 2006 champion Fernando Alonso left Renault to join McLaren, earning him and his rookie teammate, Lewis Hamilton, the numbers 1 and 2; and again in 2010 when Jenson Button moved to McLaren from Brawn GP.

If a driver wins the World Championship but does not defend his title the following season, tradition dictates that the racing number 1 is not allocated; the reigning World Champion constructor then receives numbers 0 and 2. Damon Hill received car number 0 in 1993 due to Nigel Mansell's move to the CART PPG Indy Car World Series in the U.S., and again in 1994, this time due to Alain Prost's retirement. This tradition has not always been in place; Ronnie Peterson received number 1 in the 1974; although he did not win the championship the previous year, due to Jackie Stewart's retirement, his Lotus team was allowed to keep Number 1 as they had won the constructors' title.

The 2014 season was the first with a new system, in which drivers are assigned numbers for their entire careers. Under this system, similar to that used in MotoGP, drivers may choose any (available) number from 2 to 99, with number 1 reserved for the reigning Drivers' Champion. The champion's "regular" number is placed in reserve while that driver is using number 1, preventing other drivers from using that number. Since Jules Bianchi's fatal accident at Suzuka in 2014, Formula One has not issued Bianchi's number 17 as a mark of respect.

A similar system is used in many European-style championships at national and international level; the champion receives number 1, and others are allocated either by a driver's placing in the previous season (third place the year before equates to race number 3) or by the team's placing in the Team/Constructor championship. If the championship driver does not return, the championship team will be allowed to use number 1.

IndyCar

During the USAC era of Indy car racing, it was traditional for the defending national champion to carry No. 1 during the season. This rule had one exception; at the Indianapolis 500. The previous year's Indy 500 winner traditional utilized No. 1 in the Indy 500 that particular year. The defending national champion would have to select a different car number for Indy only, unless he happened to also be the defending Indy 500 winner, sometimes swapping numbers with the other affected driver. There were typical exceptions to the rule, as some defending champions decided against using No. 1, preferring instead to maintain their identity with their favorite number.

During the CART era, car numbers 1–12 were assigned based on the previous season's final points standings. Number 13 was not allowed, and starting in 1991, No. 14 was formally assigned to A. J. Foyt Enterprises. The remaining numbers 15–99 were generally allocated to the rest of the teams on first-come, first-served basis. Some teams in the top 12 chose not to utilize their assigned number, instead preferring a personal favorite number, an example being Newman-Haas Racing exchanging the #2 with Walker Racing to get the #5 after Nigel Mansell joined the team, #5 having been his long-used number in Formula One. "Unused" numbers from 1–12 reverted to the general pool, and could be used by any of the remaining teams. Again at Indianapolis only, the No. 1 was set aside for use by the defending Indy 500 winner, if he so choose to use it, since it was a USAC-sanctioned race.

In the current Indy Racing League LLC era, No. 1 is set aside for use by the previous season's championship entry (team, Rule 4.4B). However, the majority of champions since 1998 have ignored the tradition. Teams and/or sponsors often requests to keep their normal numbers in order to maintain their team identity, similar to NASCAR, and some drivers have used their car numbers in social media accounts. The 1998 IRL championship team was A. J. Foyt Enterprises, which kept the traditional #14, while Panther Racing kept the #4 identified with team minority owner Jim Harbaugh, who wore #4 for the majority of his NFL career (except for his year in Charlotte, where John Kasay wore that number, he wore Foyt's #14). In one case, at the 2012 Indianapolis 500, defending national champion Dario Franchitti, who normally used #10, and had the right to #1, chose to use #50 at that race for the 50-year anniversary of sponsor Target, which has been car owner Chip Ganassi's sponsor since 1990.

Other sports

Number 21 on the road bicycle of Ellen van Dijk at the Ronde van Drenthe.

Other sports which feature players with numbered shirts, but where the number that may be worn is not relevant to the player's position and role are:

• Athletics
• Cycling
• Field hockey
• Lacrosse
• Team handball
• Roller derby
• Volleyball

In water polo, players wear swim caps bearing a number. Under FINA rules, the starting goalkeeper wears Number 1, the substitute goalkeeper wears Number 13, and remaining players wear numbers 2 though 12. In road bicycle racing, numbers are assigned to cycling teams by race officials, meaning they change from race to race. Each team has numbers in the same group of ten, excluding multiples of ten, for example 11 through 19 or 21 through 29. If a race has squads of smaller than nine, each still uses numbers from the same group of ten, perhaps 31 through 36 where the next squad will have 41 through 46. Usually, but not always, the rider who wears a number ending in 1 is the squad's leader and the one who will try for a high overall placing. If the race's defending champion is in the field, he or she wears number 1.

In floorball all players are required to have number between 1–99 on their jersey, but goalies are the only players who can wear number 1.

Retired numbers

Main article: Retired number

Jackie Robinson in his now retired number 42 jersey.

Retiring the uniform number of an athlete is an honor a team bestows on a player, usually after the player has left the team, retires from the game, or has died. Once a number is retired, no future player from the team may use that number, unless the player so-honored permits it. Such an honor may also be bestowed on players who had their careers ended due to serious injury. In some cases a number can be retired to honor someone other than a player, such as a manager, owner or a fan. For example, the Boston Celtics retired the squad number 1 in honor of the team's original owner Walter A. Brown.

See also

• Competition number in individual sports

External links

• English football's experiments with numbering
• Article in The Guardian about the Number 1 goalkeeper jersey
• Overcompetitive.com – tongue-in-cheek look at the traditions behind numbers 1 to 11 in football
• Baseball Hall of Fame, with uniform numbers
• Retired numbers for NFL franchises
• More than just a number? The importance of a squad number.