The game of football can be unpleasant.
Stanford quarterback K.J. Costello found that out the hard way on Saturday afternoon during the Cardinal's game against Northwestern.
Costello took the snap and saw an opening right up the middle of the Wildcats defense. He ran for a few extra yards and then slid to the ground to avoid a defender.
Northwestern defensive lineman Earnest Brown wasn't having any of the slid. Despite Costello clearly giving himself up on the play, Brown sent a forearm shiver right to Costello's face mask.
The Stanford quarterback's helmet popped off as his head hit the ground.
Here's the play.
Despite the clear and obvious infraction by Brown, officials did not remove him from the game. In an era where college football fans hate to see players leave the game because of the new targeting rule, this one should have been easy.
As for Costello, the quarterback went to the locker room. He's likely headed for the concussion protocol, but no diagnosis has been announced yet.
Costello completed 16-of-20 passes for 152 yards and a touchdown before leaving the game.
The Cardinal currently hold a 10-0 lead over Northwestern at the half.
Stay tuned for an update on Costello.