Multiple outlets are reporting that Lions quarterback Drew Stanton separated his left shoulder during Sunday's win against the Buccaneers. The injury is reported as being a Grade 3 separation of his AC joint, an injury Matthew Stafford has dealt with multiple times in the last two seasons on both shoulders.
Because the injury happened to Stanton's non-throwing shoulder, it's possible he could play on Sunday against the Dolphins. After all, last season Stafford played on Thanksgiving after separating his left shoulder just four days earlier, so a quick turnaround isn't out of the question with an injury to a quarterback's non-throwing shoulder. It's likely that Jim Schwartz won't name a starter until Sunday (at least not publicly), although that's what happened last week and Stanton wasn't even hurt, so this new injury probably won't factor into his timetable.
I don't know what Lions quarterbacks did to piss off the football gods, but this is getting beyond ridiculous. Stafford hurt his knee and his left shoulder last season, and then this year he has injured his right shoulder twice. Also this season, Shaun Hill broke his arm and a finger on his throwing hand, which is why Stanton was forced into action in the first place.
If Stanton is unable to play because of this injury, I would imagine Hill would be the starter since he was active yesterday. Even if Stanton didn't get hurt it's possible Hill would have been the starter this week, but only Jim Schwartz knows that for sure. I'd be inclined to guess he would stick with the hot hand and the guy who led the Lions to two consecutive wins, but now another injury will have to be factored into the decision about which QB to start.