*Note: All data is from the 1985 tournament to the present.
The 2017 tournament wasn't kind to the No. 2 seeds. Duke and Louisville were bounced in the second round by No. 7 seeds in South Carolina and Michigan, respectively. Arizona lost to No. 11 seed Xavier in the Sweet 16.
Only Kentucky held true to its projected outcome, speaking strictly in terms of seed line. The Wildcats advanced to the Elite Eight, where they fell 75-73 to No. 1 seed North Carolina.
All this goes to show you: there’s no certainty when it comes to the No. 2 seed.
The 1991 Syracuse team learned that lesson quickly. The Orange dropped a 73-69 loss to No. 15 seed Richmond, the first time ever a No. 2 seed was sent home in the opening round.
Before the Spiders’ upset, the second seeds didn’t have much trouble defeating the No. 15 seeds. From the expansion to 64 teams in 1985 until the Syracuse upset, only four games had been decided by eight points or fewer.
But the 1991 Orange showed that perhaps beating a No. 2 wasn't nearly improbable as the 1 versus 16 games.
All in all, No. 2 seeds have lost only eight games in the opening round, most recently Michigan State in 2016 when the Spartans lost to Middle Tennessee 90-81. However, three of those losses happened in back-to-back years with Duke and Missouri in 2012 and Georgetown in 2013.
The Blue Devils have the most appearances in the two spot with nine. The 2012 loss to Lehigh has been the only setback, although in 1997 and 2008, Duke survived Murray State and Belmont respectively by a combined four points.
More two seeds have been knocked out in the second round (41 of the 124 first-round winners) than any other round in the tournament, but five No. 2 seeds have won a national championship: 1986 Louisville, 1991 Duke, 1998 Kentucky, 2004 Connecticut, and 2016 Villanova.