In an online contest called March Melee that includes hundreds of users, 35,200 brackets were filled out. What percentage picked Northern Iowa to reach the Sweet 16? Less than .01 percent. What percentage picked St. Mary's to get this far? Less than .20 percent. The odds have shrunk considerably that one of those two mid-major upstarts will win its regional semifinal Friday night to move within 40 minutes of a spot in the Final Four.

Tennessee vs. Ohio StateLast team standing

The Midwest has been the most volatile of the regionals with only one of the top four seeds - No. 2 Ohio State - still alive. "We definitely thought it was crazy that it happened," Ohio State's multi-tasking guard Evan Turner said of top-seeded Kansas' elimination in the second round. Although the Buckeyes' path to the Final Four doesn't seem to have many formidable obstacles, they better not overlook a talented but inconsistent Tennessee team. The Vols' aggressive defense will annoy the turnover-prone Buckeyes, who don't have a classic point guard.

Northern Iowa vs.

Michigan StateRole reversalUNI was able to play loosey-goosey as the lightly regarded warm-up act on Kansas' road to the Final Four. Now the Panthers' profile has been raised and we'll see if they've come down to Earth as only slight underdogs to wounded Michigan State. Ali Farokhmanesh & Co. will face a Michigan State team that must replace star guard Kalin Lucas, who ruptured his Achilles tendon in the Spartans' last-second win over Maryland. Lucas' replacement, sophomore Korie Lucious, hit the buzzer-beater that sent Michigan State to the Sweet 16.

St. Mary's vs. Baylor

Enter Samhan

St. Mary's center Omar Samhan leads the tournament in scoring and one-liners. He totaled 61 points and shot 75 percent in wins over Richmond and Villanova and never stopped talking both during the games and after them in the interview sessions. His thoughts on being a big man (6-11, 260) who likes to play in the post: "I think the paint's sexy." On being matched against Baylor's Ekpe Udoh: "He can jump, and I can't. He's fast, and I'm not. He's strong, and I'm not. Although I'll have trouble guarding him, he'll have trouble guarding me."

Purdue vs. Duke Floor burns

The Boilermakers' chances of going deep into the tournament were supposed to be kaput when Robbie Hummel tore the ACL in his right knee last month. So how have they reached the Sweet 16 without their most versatile player? Dee-fense! Purdue is 5-2 since Hummel went down on Feb. 24, allowing its opponents to shoot a combined 38.7 percent from the field. The Boilermakers' defensive intensity is epitomized by guard Chris Kramer, whose massive elbow pads offer him some protection in scrums for loose balls.

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