Baltimore Ravens tight end Dennis Pitta has suffered a concussion and did not return to the Ravens' 13-10 victory over the Pittsburgh Steelers on Sunday.
Pitta left the game in the first quarter and returned to the locker room to be examined after being shaken up.
Steelers running back Isaac Redman also left the game with a concussion and did not return.
Steelers defensive lineman Ziggy Hood suffered a lower back injury in the first half, and did not return to the game.