“Next question” makes guys look like Terrell Owens, I.e., an idiot.
A “I’m just focused on the team and contributing to wins” works just fine.
Yeah, I have zero problem with a guy wanting to start and even saying so. "Well I would like to start, and I think I'm a starter in this league, but I'm focused on doing anything the coach wants to help the team win! And if that means coming off the bench right now, then I'm good with that." -- that kind of thing is standard stuff and the kind of ambition to be better that you _want_ to hear from players.
"No comment." is a bit passive aggressive.