INDIANAPOLIS (AP) - Colts receiver Austin Collie has now been diagnosed with at least his third concussion in less than 22 months.

Coach Chuck Pagano says Collie returned to the team complex Monday and "felt good," but the team would not use him again until he was cleared to play by the team's medical staff.

Collie missed seven of the final eight regular-season games in 2010 season after sustaining two other concussions.

That appears to be the most significant injury Indy took in Sunday night's 26-24 loss at Pittsburgh.

Pagano says an MRI on defensive end Cory Redding's left knee revealed a mild sprain of the medial collateral ligament. He will likely miss one week. Pagano also says linebacker Robert Mathis is "fine" after leaving in the first quarter with a strained shoulder.