The 1972 NCAA University Division football season saw the USCTrojans, coached by John McKay, go undefeated and win the national championship as the unanimous choice of the fifty AP panelists. Eighth-ranked in the preseason, the Trojans were narrowly voted #1 in the first AP poll, and stayed out front for the rest of the year.
During the twentieth century, the NCAA had no playoff for the major college football teams in the University Division, which became Division I in 1973 (and Division I-A in 1978). The NCAA Football Guide, however, did note an "unofficial national champion" based on the top ranked teams in the "wire service" (AP and UPI) polls. The "writers' poll" by Associated Press (AP) was the most popular, followed by the "coaches' poll" by United Press International) (UPI). Through the 1973 season, the UPI issued its final poll in early December before the bowls, but since 1968 (and 1965) the AP Trophy was withheld until the postseason was completed. The AP poll in 1972 consisted of the votes of fifty sportswriters, though not all of them voted in every poll. Those who cast votes would give their opinion of the ten best teams. Under a point system of twenty points for first place, nineteen for second, etc., the "overall" ranking was determined.
This season was historically significant because it was the first in which freshmen were eligible to play varsity football in the University Division. The NCAA had historically prohibited freshmen from varsity competition, except during the U.S. involvement in World War II. In 1968, the NCAA allowed freshman eligibility in the University Division in all sports, except football and basketball, and extended the rule to those sports effective with the 1972–73 academic year.
This was the last season for the "University" and "College" divisions. For the 1973 season, the NCAA created the three-division structure that exists today with teams and conferences designated accordingly:
Five years later in 1978, Division I was subdivided (for football only) into I-A and I-AA. In 2006, these were renamed Division I FBS and FCS, respectively. Many of the teams and conferences now in FCS (Big Sky, Ohio Valley, SWAC, Yankee) were initially in Division II and moved up to I-AA.
On September 9, #1 Nebraska lost 20–17 on a late field goal to unranked UCLA at night in Los Angeles and dropped to tenth place. #2 Colorado beat California 20–10. #3 Ohio State was idle, and #4 Arkansas lost 31–10 to #8 USC in Little Rock. #5 Penn State had not begun its season and fell to sixth. #7 Alabama beat Duke 35–12 in Birmingham, reached the top five, as did #6 Oklahoma, which had not yet played a game and moved up two slots. In the next poll, USC received 13 first place votes, and Colorado and Oklahoma had 12 apiece, but USC had a narrow lead in points, 779 to Colorado's 769. The poll was: 1.USC 2.Colorado 3.Ohio State 4.Oklahoma 5.Alabama
September 16: #1 USC trounced Oregon State 51–6, and #2 Colorado was idle. #3 Ohio State blanked Iowa 21–0, and #4 Oklahoma shut out Utah State 49–0. #5 Alabama was idle, and #7 Tennessee took its place in the next poll: 1.USC 2.Oklahoma 3.Colorado 4.Ohio State 5.Tennessee
September 23: #1 USC won 55–20 at Illinois, and #2 Oklahoma crushed Oregon 68–3. #3 Colorado won 38–6 at Minnesota, #4 Ohio State was idle, and #5 Tennessee beat Wake Forest 45–6. The poll was 1.USC 2.Oklahoma 3.Colorado 4.Tennessee 5.Ohio State
September 30: #1 USC played another Big Ten opponent, beating Michigan State 51–6 at the Coliseum in Los Angeles. #2 Oklahoma beat Clemson 52–3, having outscored its first three opponents 169–6. #3 Colorado lost 31–6 at Oklahoma State, and #4 Tennessee lost 10–6 to Auburn in Birmingham. #5 Ohio State beat North Carolina 29–14. #6 Alabama beat Vanderbilt 48–21, and #8 Michigan defeated Tulane 41–7, and both returned to the top five. The poll was 1.USC 2.Oklahoma 3.Ohio State 4.Alabama 5.Michigan
October 7: #1 USC won 30–21 at Stanford; the nine-point margin of victory was the closest of their perfect season. #2 Oklahoma was idle, and #3 Ohio State won 35–18 at California. #4 Alabama won 25–7 at Georgia and #5 Michigan beat Navy 35–7. The poll was 1.USC 2.Oklahoma 3.Alabama 4.Ohio State 5.Michigan
October 14: #1 USC went back to winning big, 42–14 over California. #2 Oklahoma shut out rivalTexas 27–0 at Dallas, and #3 Alabama beat Florida 24–7. #4 Ohio State beat Illinois 25–7, and #5 Michigan blanked Michigan State 10–0, but dropped to sixth, replaced by #6 Nebraska, which rolled over Missouri 62–0. The poll was 1.USC 2.Oklahoma 3.Alabama 4.Ohio State 5.Nebraska
October 21: #1 USC beat Washington 34–7, but #2 Oklahoma yielded its first touchdown of the season at Colorado, and eventually fell 20–14. #3 Alabama won at Tennessee 17–10, #4 Ohio State won at Wisconsin 28–20, and #5 Nebraska won 56–0 at Kansas to continue its rise in the polls. #6 Michigan won 31–7 at Illinois and returned to the top five. The poll was 1.USC 2.Alabama 3.Nebraska 4.Ohio State 5.Michigan
October 28: #1 USC won 18–0 at Oregon, its only shutout in a perfect season. #2 Alabama beat Southern Mississippi 48–11 in Birmingham, and #3 Nebraska registered its fourth consecutive shutout, 34–0 at Oklahoma State. Including a 77–7 win at Army, the Cornhuskers had outscored their opponents 271–14 after their opening loss. #4 Ohio State handled Indiana 44–7, and #5 Michigan beat Minnesota 27–19. The poll was 1.USC 2.Alabama 3.Nebraska 4.Michigan 5.Ohio State
November 4: #1 USC beat Washington State 44–3 in Seattle, and #2 Alabama defeated Mississippi State 58–14. #3 Nebraska won 33–10 at Colorado, #4 Michigan won 21–7 at Indiana, and #5 Ohio State beat Minnesota 27–19. The poll remained unchanged at: 1.USC 2.Alabama 3.Nebraska 4.Michigan 5.Ohio State
November 11: #1 USC had the week off, and #2 Alabama beat LSU 35–21 at Birmingham. #3 Nebraska visited Iowa State and played to a 23–23 tie. #4 Michigan won 31–0 at Iowa to extend its record to 9–0. #5 Ohio State lost 19–12 at Michigan State, and #7 Oklahoma beat Missouri 17–6 to return to the top five. The poll was: 1.USC 2.Alabama 3.Michigan 4.Oklahoma 5.Nebraska
November 18: #1 USC beat #14 UCLA, 24–7, and #2 Alabama beat Virginia Tech 52–13. #3 Michigan got past Purdue 9–6, #4 Oklahoma won 31–7 at Kansas and #5 Nebraska beat Kansas State 59–7. The top nine stayed unchanged; the top five: 1.USC 2.Alabama 3.Michigan 4.Oklahoma 5.Nebraska
November 25: #1 USC and #2 Alabama were idle, while #3 Michigan (10–0) and #9 Ohio State (9–1) met at Columbus to determine the Big Ten title and the Rose Bowl berth. Ohio State won 14–11, and #4 Oklahoma returned the favor of last year's Game of the Century, and beat #5 Nebraska 17–14 on the road in Lincoln. Oklahoma accepted a bid to the Sugar Bowl to face #6 Penn State, which beat visiting Pittsburgh 49–27 to close its regular season at 10–1. The poll: 1.USC 2.Alabama 3.Oklahoma 4.Ohio State 5.Penn State
December 2: #1 USC closed its regular season at home with a 45–23 win over Notre Dame to finish at 11–0. #2 Alabama (10–0) was preparing to do the same as it met Auburn (8–1) in their annual Iron Bowl rivalry game in Birmingham. Auburn spoiled perfection, beating Alabama 17–16, and #3 Oklahoma closed its regular season with a 10–1 record after a 38–15 win over Oklahoma State. #4 Ohio State and #5 Penn State had both finished their regular seasons. The final regular season poll was: 1.USC 2.Oklahoma 3.Ohio State 4.Alabama 5.Penn State.
In 1972, only the Rose Bowl (Big Ten vs. Pac-8) and Cotton Bowl (SWC winner) had rigid conference tie-ins. Thus, Big 8 champion Oklahoma passed up an Orange Bowl invitation to play in the Sugar Bowl, while SEC champion Alabama passed the Sugar to meet Texas in the Cotton. For the first time, the Sugar Bowl was played at night on New Year's Eve, rather than New Year's Day afternoon. With two consecutive victories in the Orange Bowl, #9 Nebraska was invited to a third against #12 Notre Dame.
Prior to 1973, the NCAA was divided into two divisions, University and College. College Division teams (also referred to as "small college") were ranked in polls by the AP (a panel of writers) and by UPI (coaches). The national champion(s) for each season were determined by the final poll rankings, published at or near the end of the regular season, before any bowl games were played.