Only 14 times in the 131-year history of Oklahoma football have the Sooners finished the season without a single loss. Eleven of the 14 unbeaten seasons are shared by OU's four winningest head coaches.
Oklahoma's last unbeaten season and the only time the Sooners have won as many as 13 games in a single season was in OU's 2000 national championship season. That occurred in Bob Stoops' second season as head coach of the Sooners and following a 7-5 season in 1999.
Stoops had six 12-win seasons and six 11-win teams in his 18 seasons as the Oklahoma head coach, but just twice did he lose as few as one game in a season (in 2000 and in 2004, when the Sooners were 12-0 before losing to USC in the BCS national championship game).
Barry Switzer has the highest winning percentage of Oklahoma's four legendary head coaches (157-29-4, .837) but just two of his Sooner teams finished the season without a loss (10-0-1 in 1973 and 11-0 in 1974). The Sooners were 32-1-1 in Switzer's first three seasons as head coach. Five OU teams under Switzer ended the year with just one loss.
Bud Wilkinson and the late, great Bennie Owen, who served not only as the head football coach of the Sooners in the early 1900s but also the basketball and baseball coach, shared the notoriety of being the only Oklahoma head coach to go undefeated as many as four times in his OU coaching tenure.
Wilkinson's teams were unbeaten in 1949, 1954, 1955 and 1956, and six other times his teams suffered just one loss. Owen was the head coach of Oklahoma football for 22 seasons from 1905 to 1926, and his teams were unbeaten in four of them (1911, 1915, 1918 and 1920).