No. 11 seed Xavier (23-13) vs. No. 2 seed Arizona (32-4)
Bottom line: Xavier is the lone double-digit seed left in a Sweet 16 filled with power programs. The Musketeers pulled off a pair of upsets to reach the regional semifinals, beating No. 6 seed Maryland and No. 3 Florida State the first weekend of the tournament. To get to the next round, Xavier will have to beat one of the hottest teams in the bracket. Arizona earned a share of the Pac-12 regular-season title, won the Pac-12 Tournament, then beat North Dakota and Saint Mary’s in the NCAA Tournament. Miller and Mack: Arizona coach Sean Miller and Xavier’s Chris Mack will be facing each other in regional semifinals for the second time in three years. The two are close; Mack was an assistant under Miller and was elevated to the head job when he left for Arizona. Keep an eye on: Xavier’s Trevon Bluiett and Arizona’s Lauri Markkanen. Bluiett struggled with injuries during the regular season, but has rounded back into form at the right time, leading the Musketeers into the regional semifinals despite a season-ending injury to point guard Edmond Sumner in late January. Markkanen is a difficult matchup for any team, a 7foot freshman playing with the skills of a guard and can shoot from inside or out.