In order of preference:
1.) Bobby Petrino
2.) Dan Mullen
3.) Kyle Whittingham
4.) Mark Hudspeth
5.) Gus Malzahn
This is a realistic list, IMO. If Jon Gruden does not happen, which it probably will not, Tennessee is going to have a hard time getting anything better. Not because the program isn't good enough, but more so because coaches like Patterson, Peterson, Strong, Etc... have ties to the players and programs they are coaching at. Alot of coaches, at least the ones worth having, don't just jump ship at the first sound of the money truck. They have made commitments to their current programs and feel an obligation to stick with them. Dan Mullen may fall under this very category. It is going to be a tough pull. I say if Gruden turns UT down, go after Petrino. You hope that he has learned his lesson in Arkansas and UT reaps the reward. Since that probably will not happen, UT needs to go after a young, high energy, aggressive, successful, complete football coach at the mid major level. Urban Meyer, Nick Saban, and Jim Tressel all started somewhere. It can happen at UT as well. Mark Hudspeth, Doeren, and Gus Malzahn would all be viable options.