While 12-5 upsets seem to demand the most media attention, it's possible that the 13-4 upset is the more important one to figure out in recent years.
4-seeds went 4-0 in the first round last year, but in two of the three years before that, they split their matchups against 13-seed opponents.
Indeed, this year there are some potential first-round shockers on the board, according to Vegas bookmakers.
No. 13 Kent State is just a 4.5-point underdog to No. 4 Indiana heading into the opening weekend of the tournament.
The Golden Flashes have lost just six times all year, and have played tough with quality opponents including Gonzaga and Houston earlier in the season.
If the Hoosiers come in sleeping, they could be in for a surprise.