Andrew Luck suffered a concussion in the Indianapolis Colts' 24-17 win over the Tennessee Titans. Clayton Geathers also suffered a concussion.

"Well after we were all done with the locker room, both guys didn't feel right and went in the training room, and both were evaluated for concussions. Both are in the protocol," said Chuck Pagano.

Luck was sacked twice and hit eight other times against the Titans. He is believed to have suffered the concussion when Titans defensive tackle Austin Johnson landed on top of him after recording a sack with 11:46 remaining in the game.

Scott Tolzien will start for the Colts in Week 12 if Luck is unable to play.