By any measure, Middle Tennessee's upset was one for the ages

Middle Tennessee, at 16.5 points, was the fourth-biggest underdog to win in the NCAA tournament in the past 20 seasons. Jeff Curry/USA TODAY Sports

No. 15 seed Middle Tennessee threw the NCAA tournament for a loop Friday with a 90-81 win over No. 2 seed Michigan State.

The Blue Raiders’ win was the eighth by a 15-seed over a 2-seed, an outcome possible since the tournament expanded to 64 teams in 1985.

The seeds don’t tell the entire story of this upset. According to Westgate, Michigan State entered the NCAA tournament with 9-2 odds and as the co-favorite with Kansas to win the title. Middle Tennessee closed as a 19-1 underdog (+1900) for the first-round game in St. Louis.

In ESPN’s Tournament Challenge, 97.8 percent of brackets had the Spartans winning this game, and 22.3 percent predicted they would win the national championship.

Based on pretournament adjusted efficiency, which comes courtesy of KenPom.com, Michigan State had an advantage of 23.3 points per 100 possessions over Middle Tennessee. That makes Thursday’s result the second-largest upset in the past 15 years, by this measure, behind Norfolk State’s win over No. 2 seed Missouri in 2012 (27.5 points per 100 possessions).

The Blue Raiders had been 0-22 against teams in the top 10 of The Associated Press poll.