The 10 biggest NCAA tournament upsets of the past 20 years

Norfolk State's 2012 victory as a 15-seed over Missouri is the biggest upset in the past 20 years in the NCAA tournament -- and it wasn't even the only 15-seed over a 2-seed that day. Eric Francis/Getty Images

In the past 20 NCAA tournaments, there have been 27 double-digit underdogs that have won outright. But how many were truly big upsets according to the point spread?

Below, we run through the 10 biggest tournament upsets according to the point spread from 1996 to this year's tourney.

1. March 16, 2012 -- round of 64

No. 15 Norfolk State Spartans vs. No. 2 Missouri Tigers

Closing line: Missouri -21.5

The biggest tournament upset win in the past 20 years belongs to Norfolk State, which defied the 21.5-point spread and shocked Missouri. The Spartans were led by Kyle O'Quinn, who scored a game-high 26 points to go along with 14 rebounds. Up two with 3.8 seconds left, O'Quinn, despite his great game, missed two free throws and opened the door for the Tigers. Phil Pressey, however, missed a potential game-winning 3-pointer at the buzzer, and Norfolk State had officially shocked the college basketball world.

It turned out to be one of two wins by a 15-seed over a 2-seed that day -- the only time that has happened in tournament history -- as No. 15 Lehigh beat No. 2 Duke as a 12-point underdog.

Final score: Norfolk State 86, Missouri 84

2. March 14, 1997 -- round of 64

No. 15 Coppin State Eagles vs. No. 2 South Carolina Gamecocks

Closing line: South Carolina -18.5

Coppin State became the third-ever 15-seed to win a tournament game, as the Eagles stunned SEC regular-season champion South Carolina. The game was tied at halftime, and South Carolina opened up a seven-point lead in the second half. After that, Coppin State outscored South Carolina 38-18 in the final 13 minutes to win by 13. The margin remains the largest by a 15-seed in a tournament game. It was also the first tournament win for both Coppin State and the MEAC conference as a whole.

Final score: Coppin State 78, South Carolina 65

3. March 15, 2001 -- round of 64

No. 15 Hampton Pirates vs. No. 2 Iowa State Cyclones

Closing line: Iowa State -17.5

Despite coming off an early exit in the Big 12 tournament, Iowa State was expected to roll over Hampton. The game marked the first tournament appearance for the Pirates, who were in their sixth season as a Division I program. Hampton's Tarvis Williams put his team up one with 6.9 seconds left, and Iowa State's Jamaal Tinsley missed a layup at the buzzer. The Pirates pulled the upset despite shooting 38.9 percent from the field and 15 percent from 3.

Final score: Hampton 58, Iowa State 57

4. March 18, 2016 -- round of 64

No. 15 Middle Tennessee Blue Raiders vs. No. 2 Michigan State Spartans

Closing line: Michigan State -16.5

After winning the Big Ten conference tournament, big things were expected from Denzel Valentine and Michigan State. Instead, Tom Izzo's squad never led against Middle Tennessee and went down in shocking fashion, losing as a -9000 favorite.

Final score: Middle Tennessee 90, Michigan State 81

5. March 19, 2015 -- round of 64

No. 14 UAB Blazers vs. No. 3 Iowa State Cyclones

Closing line: Iowa State -14

Fourteen seasons after being stunned by Hampton, another highly seeded Iowa State team fell as a double-digit favorite in the round of 64. The Cyclones had an early 10-point lead, but in the second half neither team could get a lead of more than four points. The Blazers closed the game on a 9-4 run in the final 1 minute, 40 seconds to win by one. It was the second time in 12 seasons that they won a tournament game as a double-digit underdog; UAB beat top-seed Kentucky as a 10-point underdog in 2004.

Final score: UAB 60, Iowa State 59

6. March 22, 2013 -- round of 64

No. 15 Florida Gulf Coast Eagles vs. No. 2 Georgetown Hoyas

Closing line: Georgetown -14

Georgetown lost as a double-digit favorite in the tournament for the second time in four years -- this time at the hands of Florida Gulf Coast. The Eagles were making their first tournament appearance in just their second year of eligibility. After Florida Gulf Coast led 24-22 at halftime, "Dunk City" came alive in the second half, as the Eagles scored 54 points en route to a 10-point win. How unlikely was their Eagles' 54-point second half? Georgetown entered the tournament allowing 55.7 PPG.

Final score: Florida Gulf Coast 78, Georgetown 68

7. March 18, 2010 -- round of 64

No. 14 Ohio Bobcats vs. No. 3 Georgetown Hoyas

Closing line: Georgetown -13.5

The Bobcats' starting backcourt of D.J. Cooper and Armon Bassett combined for 55 points as they dominated the favored Hoyas. They led 48-36 at halftime and held a lead of at least seven points for the entire second half. Their 97 points remain the most ever by a team seeded 13th or lower in the tournament.

Final score: Ohio 97, Georgetown 83

8. March 18, 2005 -- round of 64

No. 14 Bucknell Bison vs. No. 3 Kansas Jayhawks

Closing line: Kansas -13.5

This upset was more than just a 13.5-point spread -- it pitted one of college basketball's blue bloods against a small school in central Pennsylvania. Kansas was the preseason No. 1 going into the 2004-05 season, and it had won at least one game in each of its previous 15 tournaments. Bucknell, on the other hand, had lost its only two tournament games in school history by an average of 27.5 PPG. None of that mattered on this Friday night in Oklahoma City. The Bison's Chris McNaughton rattled in a hook shot with 10.5 seconds left, and Bucknell survived a pair of potential game-winners from Kansas to pull off the shocker.

Final score: Bucknell 64, Kansas 63

9. March 21, 2014 -- round of 64

No. 14 Mercer Bears vs. No. 3 Duke Blue Devils

Closing line: Duke -13

For the second time in three seasons, Duke was upset as a double-digit round-of-64 favorite. In 2012, C.J. McCollum and Lehigh beat Duke as a 12-point underdog. This time, it was Atlantic Sun Conference champion Mercer knocking off Duke. The Bears came back from five points down with 4:40 to go, finishing the game on a 20-8 run. It was the second straight season the Atlantic Sun champion won as a big underdog, following Florida Gulf Coast's victory over Georgetown in 2013.

Final score: Mercer 78, Duke 71

10. March 21, 2002 -- Sweet 16

No. 5 Indiana Hoosiers vs. No. 1 Duke Blue Devils

Closing line: Duke -13

In the only Sweet 16 game to make the list, Indiana overcame a 17-point deficit to beat defending champion Duke in a wild game. It appeared over when Indiana took a four-point lead with 11.1 seconds left, but on the ensuing possession, Duke's Jason Williams was fouled while making a 3-pointer with 4.2 seconds left. He missed the free throw, though, and the Hoosiers pulled off the massive upset.

Final score: Indiana 74, Duke 73

Honorable mention

March 29, 1999 -- national championship game

No. 1 Connecticut Huskies vs. No. 1 Duke Blue Devils

Closing line: Duke minus-9.5

In the past 20 seasons, the biggest underdog to win a national championship game was Connecticut in 1999, when it snapped Duke's 32-game winning streak as a 9.5-point underdog. UConn did not trail for the final 14:25, winning its first national title behind 27 points from Richard Hamilton. The Huskies were underdogs twice all season in 1998-99 -- by 9.5 points against Duke, and by 11 points against Maryland earlier in the season. Both times they won outright.

Final score: Connecticut 77, Duke 74

March 11, 1999 -- round of 64

No. 14 Weber State Wildcats vs. No. 3 North Carolina Tar Heels

Closing line: North Carolina -13

North Carolina hadn't lost an opening-round game in the tournament since 1980, but it was playing a Weber State team that had the perfect formula for an upset -- an unbelievable individual performance and great 3-point shooting. The individual performance came from Harold Arceneaux, who carried the Wildcats with 36 points -- nearly half of the team's total. The Wildcats made 14 of their 26 3-pointers, including 7 of 10 in the second half. The win gave Weber State its second win as a 14-seed over a 3-seed in five years; it is the only team to win more than one game as a 14 over a 3 in tournament history.

Final score: Weber State 76, North Carolina 74