Butler is going to Houston because they continued their incredible two-season run of success in close NCAA tournament games. Connecticut's going because they continued their incredible nine-game run of success in the 2011 postseason.
When the field of 68 teams was announced 14 days ago, Ken Pomeroy estimated that the Huskies had just a seven percent chance of making the Final Four. For the Bulldogs the odds were even longer: one percent. This Butler team is one in a hundred.
(8) Butler 74, (2) Florida 71 (OT) [67 possessions]
Butler looked so bad for long stretches of this game that Gus Johnson, Len Elmore, and Reggie Miller were sketching out epitaphs for this Bulldog team by midway through the second half. Brad Stevens' team was lofting attempted threes over the taller Gators -- who even when they weren't playing zone started many possessions in a man disguised to look like a zone -- and those threes weren't falling. In the first 33 minutes of the contest Butler had flung 27 of the things at the rim and connected on just six. Meanwhile the only limitation on how many points Vernon Macklin could score for Florida was foul trouble. For the game he would record 25 points on 11-of-14 shooting to go along with four fouls -- all in just 24 minutes.
But the disparity in points between the two teams was never quite as large as it seemed like it should have been. Florida's largest lead was 11, with 9:26 to go. That was formidable, but it wasn't the kind of deficit that Marquette faced against North Carolina this weekend, or that Richmond confronted against Kansas. Then Chishawn Hopkins, whose only prior NCAA tournament experience had been a club trillion cameo against Wisconsin, hit a three with a little more than six minutes left and, for whatever reason, the game was on. Butler was within four, and from that point on the Bulldogs would hit three of their last six attempts from beyond the arc. Meanwhile Billy Donovan's team was compiling of 3-of-14 body of work on their threes. Two of those three makes came on back-to-back possessions in overtime, as Kenny Boynton and Erving Walker kept pace with an old-fashioned three-point play by Khyle Marshall, one of those newfangled threes the kids are talking about by Shelvin Mack, and four free throws from Ronald Nored. (Nored leads Division I in near-turnovers that are whistled as fouls on the opposing team.) But Walker's three, with 1:41 left in OT, was the last shot Florida made from the field. From that point on Mack personally outscored the Gators 5-1, as a three and two free throws closed the deal.
There will be ample opportunity this week to reflect on the man-bites-dog spectacle of a team from the Horizon League making back-to-back Final Fours. For now, a reminder of the company that Butler keeps in the 2000s.
UCLA: 2006, 2007, 2008
Michigan State: 1999, 2000, 2001
Florida: 2006, 2007
Michigan State: 2009, 2010
North Carolina: 2008, 2009
Kansas: 2002, 2003
Maryland: 2001, 2002
Ben Howland, Tom Izzo, Billy Donovan, Roy Williams, Gary Williams, and Brad Stevens, I salute you!
(3) Connecticut 65, (5) Arizona 63 
The last shots in this game were attempted threes by Arizona's Derrick Williams and Jamelle Horne. In real time I thought Horne's shot in particular looked good. So did Connecticut's Jeremy Lamb: "The second one, I thought it was definitely going in." Instead it skidded across the rim, and the Huskies are going to Houston.
Don't let Butler win all the improbability points here. UConn is in their second Final Four in three years, and in the season in between they didn't even make the tournament. They were 9-9 in Big East play and looked lifeless in February. Among major-conference teams, Connecticut had the least impressive regular season of any Final Four participant in at least seven years, going back to Georgia Tech in 2004 and indeed beyond. Every hoary postseason cliche about a team finding itself and starting a new season applies to this group.
In theory the intersection of Kemba Walker and Arizona's suspect interior defense figured to yield a lot of points for UConn, but in the event it was the mere fact that Jim Calhoun's team got so many bites at the apple that decided the outcome. With just five turnovers in 59 possessions and Alex Oriakhi doing his usual thing on the offensive glass (four offensive boards in 20 minutes), the Huskies were able to outscore an opponent that received just 26 minutes of playing time from a foul-plagued Derrick Williams. Connecticut has taken their seven percent chance and run with it.
John Gasaway is an author of Basketball Prospectus.
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