Having grown up a few minutes from the Michigan State campus, I’m a little bit upset about today’s upset. After two decades of Michigan State coach Tom Izzo’s amazing record in post-season play, we Spartan fans had grown to assume this was the sort of thing that only happens to Duke.

But No. 2-seeded Michigan State lost to No. 15 Middle Tennessee State in St. Louis in one of the most memorable upsets ever in the NCAA Tournament. Unlike several of the purported “upsets” earlier in the first round, where the worse-seeded team was actually the favorite, this one was a real shock. In fact, our March Madness predictions had given Michigan State a 95 percent chance to win, while Vegas had the Spartans as 16.5-point favorites.

So here’s a question I’m almost too embarrassed to ask: Was this the biggest NCAA tourney upset of all-time? The answer is that it isn’t quite, although Michigan State is possibly the best team to have lost its opening game.

According to our Elo ratings, the biggest upset since the NCAA Tournament expanded to 64 teams in 1985 was Norfolk State over Missouri in 2012; Elo would have given Norfolk State just a 1.6 percent chance to win. It isn’t that Missouri was all that great, but Norfolk State looked like an especially easy mark, having barely outscored its opponents during the regular season against one of the weakest schedules in the country.

Middle Tennessee, by contrast, can play a little bit. They beat a major conference team, Auburn, during the regular season, and came within 6 points of VCU. No, they aren’t the 1967 UCLA Bruins, but Elo would have seeded Middle Tennessee as a 14 instead of a 15. A big part of that was their .386 shooting percentage from 3-point range entering the game; that translated into 11 for 19 from behind the arc this afternoon.

However, Michigan State looked like a very strong 2-seed. Elo had the Spartans as the second-best team in the country, after Kansas, and Las Vegas betting lines had given Michigan State the second-best chance of winning the tournament. Thus, Middle Tennessee’s pregame win probability was just 5.5 percent according to Elo. Here’s the complete list of the biggest upsets:

YEAR WINNER ELO UPSET VICTIM ELO UPSET PROBABILITY 2012 (15) Norfolk State 1443 (2) Missouri 2028 1.6% 1997 (15) Coppin State 1513 (2) South Carolina 1963 5.4 2016 (15) Middle Tenn. 1638 (2) Michigan St. 2078 5.5 2013 (15) FGCU 1615 (2) Georgetown 1990 5.6 1993 (15) Santa Clara 1605 (2) Arizona 2019 6.0 1987 (14) Austin Peay 1592 (3) Illinois 2022 6.1 2001 (15) Hampton 1514 (2) Iowa State 1888 6.7 2005 (14) Bucknell 1585 (3) Kansas 1941 6.7 1995 (14) Old Dominion 1646 (3) Villanova 2021 7.0 2014 (14) Mercer 1652 (3) Duke 1967 8.5 1993 (13) Southern 1555 (4) Georgia Tech 1918 8.8 1999 (14) Weber State 1601 (3) North Carolina 1996 9.0 2015 (14) UAB 1602 (3) Iowa State 1959 9.1 2005 (13) Vermont 1650 (4) Syracuse 1999 9.4 1997 (14) Chattanooga 1593 (3) Georgia 1924 9.6 2013 (14) Harvard 1671 (3) New Mexico 1958 9.8 The biggest upsets in the men’s NCAA Tournament, since 1985

Unsurprisingly, the list is dominated by 15-seeds that beat 2-seeds. Six of the eight all-time 15-2 upsets make the list, leaving out Richmond over Syracuse in 1991 and Lehigh over Duke in 2012, which Elo doesn’t consider to have been especially unlikely. In addition to Norfolk State’s win over Missouri, Coppin State’s win over South Carolina in 1997 also rates as having been slightly more unlikely than the Michigan State result, although only barely so. Florida Gulf Coast’s win over Georgetown in 2013 and Santa Clara’s over Arizona in 1993 are in the same vicinity.

But Michigan State was the highest-rated team on the list according to Elo. Not even Tom Izzo is immune from March Madness.

CORRECTION (March 20, 12:10 p.m.): A previous version of this article gave the incorrect number of upsets by a No. 12 seed of a No. 5 seed listed in the table. The table lists six such upsets, not seven.[

Check out FiveThirtyEight’s 2016 March Madness Predictions.