Next season's Florida-Miami opener in Orlando got even more interesting Sunday night when the Hurricanes named Manny Diaz as their new head coach.Diaz probably wouldn't be in this situation without the man he'll face in his head coaching debut: the Gators' Dan Mullen.Mullen had never even heard of Diaz in 2009 when Mullen's Mississippi State team played at Middle Tennessee State, where Diaz was the defensive coordinator."I was very impressed with what they were doing defensively," Mullen said recently, after Diaz was named the head coach at Temple. "I was really impressed with how he was on the sidelines, his energy, his excitement."When Mullen needed a new defensive coordinator the next season, he interviewed Diaz and was struck by the up-and-comer's intelligence. Diaz spent the 2010 season on Mullen's staff and rejoined it in 2015 when Geoff Collins left for UF.Diaz was with Mullen for only one season before bolting for Mark Richt's staff at Miami. Three years later, he's in charge — just in time to lead the 'Canes against Mullen's Gators on Aug. 31."I know he's been around some really good head coaches," Mullen said earlier this month. "Knowing how intelligent and how sharp he is, a lot of things I did was take different notes from every program of things I really liked and things he wasn't as high on and his personality. I know he's gotten that opportunity to go do it. He's ready to step into that role, and I'm sure he's going to be really successful."