then he isn't a very good competitor. This kind of stuff is benign. It's not locker room material. "Oh no!!!! BYU says that they are going to beat Tate. Those scoundrels!!! That's it. Boys, it's time to step up and show them how wrong they are."
Seriously, let him talk. Let him run his mouth. Calling him an idiot is weak. Now, if he doesn't perform on Saturday and get's steam rolled, then call him an idiot. But it's a bit premature to criticize a player for spouting off confidence in his teammates.