In the 81-year history of the NCAA tournament, only 19 teams have ever entered the tournament with a perfect record.

The first came in 1951, when Lou Rossini led Columbia to a 21-0 regular season and an Ivy League championship. But the Lions would fall to No. 5 Illinois 79-71 in the first round of the tournament. 

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The most recent undefeated regular season was in 2015, when Kentucky — led by Karl-Anthony Towns, Devin Booker, and Aaron and Andrew Harrison — went 34-0, winning the SEC championship. The Wildcats drew a 1 seed, and cruised to the Final Four, where they were dispatched by 1-seed Wisconsin, which would lose to Duke in the national title game.

Only seven teams in the history of college basketball have won an NCAA tournament championship with a perfect record. 

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The first came in 1956, when Bill Russell averaged 20.6 points and 21 rebounds to lead San Francisco to its second straight championship, improving on the 28-1 record of 1955.

NCAA Photos
Bill Russell celebrates a perfect season and a national championship in 1956.

The feat was repeated in 1957, when North Carolina, coached by Frank McGuire and led by Lennie Rosenbluth, won 32 straight. The most impressive of those wins came in the national championship, when the Tar Heels survived three overtimes to beat Wilt Chamberlain and Kansas 54-53.

NCAA Photos
North Carolina Tar Heels basketball won a national championship in 1957Lenny Rosenbluth of North Carolina argues with a referee during the NCAA national championship game against Kansas in 1957.

Four of the undefeated titles unsurprisingly came from UCLA, which went 281-15 from 1964-1973, winning nine national championships and recording four perfect seasons to boot.

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And the most recent undefeated title came in 1976, at the hands of Indiana. Bob Knight was in his fifth year. In 1975, Knight’s fourth season with the Hoosiers, he coached the team to a perfect 29-0 regular season, before falling to Kentucky in the NCAA tournament regional finals. But he and Indiana would not be denied the next year, going 32-0 and beating Michigan 86-68 for the school’s third championship.