Unless there's a trade, a bullpen move, or two serious injuries within the Tigers' pitching staff, he's not going to see any time other than late-season call-ups. Probably no more than three or four starts the entire year.
They're already over-loaded on Starters for when Rogers comes back, because Durbin has been pitching so well in his spot. They've already got a tough call with who to take out of the rotation (probably Maroth will go to the bullpen, unless they can make a trade).
I'd love to see him cut his teeth at the major-league level, like Bonderman and Maroth did during those tough years... but now that they're in contention they don't have time or room to be letting this kid learn on the job. He's going to have to continue pitching in the minors for quite a while, until room in the rotation can actually be made for him. I'm thinking this problem is going to last well into next year as well, unless they manage to trade away Robertson, Maroth, or Durbin (for what?).