PITTSBURGH — Eric Dixon did not play the final 90 seconds of Villanova’s 71-61 victory over Ohio State on Sunday, the victory that sent the Wildcats to their fourth Sweet 16 in the last six NCAA Tournaments. It was an exit George Costanza could appreciate. There were his 13 points and eight rebounds, his blocked shot and his steal, the multiple occasions that he dived to the floor for a loose ball. And then there was this moment: Villanova up five, Ohio State having cut a 15-point deficit to two just minutes earlier, Collin Gillespie backing down a defender, Dixon crosscourt behind the three-p…