Leftwich was hit hard at the end of a key fourth quarter drive that the Steelers were on late in the period as they looked to either tie the game or take the lead with time winding down in the fourth quarter. Leftwich was hit by James Ihedigbo and was visibly shaken up by the hit.
He was evaluated by team doctors for the rib injury, but was almost immediately ready to return to the field with the game nearing its conclusion and the Steelers getting the ball back.
Leftwich, who was starting in place of the injured Ben Roethlisberger, had 189 yards passing and 31 yards rushing to go with a rushing touchdown on the night.
The Steelers were trailing 13-10 when Leftwich returned with less than two minutes remaining.