Jimmy Garoppolo has a Grade 2 AC joint injury in his right shoulder, which means a ligament was torn when he was taken down by Miami's Kiko Alonso.

Garoppolo is doubtful for Thursday night's game with Houston. He continues to have difficulty raising his right arm without pain.

Among the different levels of AC joint injuries, Grade 1 sprains are the kind that feature some stretching and fraying of a ligament but no tears. Grade 1 sprains are the ones that quarterbacks can play with fairly soon if the pain can be tolerated.

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Grade 2 injuries are two-to-four week injuries. It's rare for a player with a Grade 2 to play the ensuing week. With Garoppolo sustaining the injury Sunday, he hasn't even had a week to recover.

The Patriots were hopeful Garoppolo might be able to be on the field in some capacity against Houston but the "doubtful" listing that came down Wednesday afternoon is an indication the injury was too severe and the turnaround too tight.

Jacoby Brissett will most likely start for the Patriots. Julian Edelman, who's taken practice reps at quarterback this week, will be the backup.