Pittsburgh Steelers linebacker Ryan Shazier will not return to Sunday's game against the Seattle Seahawks due to a concussion.
Linebacker Sean Spence replaced Shazier after he left in the first half of the game to undergo concussion protocol.
Shazier recorded one tackle prior to exiting the game.
The Steelers' linebacker is one of the anchors of the front seven and it would be a devastating loss if he misses any time.