Sunday’s Vikings-Packers game featured some bizarre incidents, one of which saw cornerback Keisean Nixon knocked out cold by his own teammate.

On the other end, quarterback JJ McCarthy was accused of sacking himself, but that wasn’t nearly as bad as the play that caused Nixon’s unfortunate collision.

The 28-year-old CB was looking to force wide receiver Justin Jefferson out of bounds with a shove, but also ran into a teammate on the sideline, who, for some reason, lowered a shoulder into him, leaving him floored.

Check it out in the video below:

“Unfriendly fire… What not to do if you can’t get out of way,” NFL doctor David J. Chao tweeted. “1) #95 don’t lower your shoulder, 2) #91 don’t push guy into player, Up to sidelines to be aware. Defender focused on play.”

Nixon exited the game with a stinger that ultimately ruled him out in what’s a massive blow where the Green Bay secondary is concerned.

“Packers CB Keisean Nixon has been ruled out for the game with a stinger. Another challenge for the short-handed corner group,” NFL Network’s Tom Pelissero reported.

This is hardly the way one ever expects to leave a game.