Steelers fullback Derek Watt appeared to be knock out cold after trying to make a tackle on the punt coverage team on Monday Night Football.
On a first quarter punt, Watt dove at Bengals returner Alex Erickson's feet. Watt's head smashed into Erickson's knee, leaving Watt laid on his back and not moving as teammates and trainers hovered over him trying to help.
Watt eventually walked to the sideline with some assistance, but didn't return to the game, which the Steelers lost 27-17.
Concerned older brother J.J., tweeted a hopeful update during the game.
Worst feeling you can ever have watching a football game.