That crack you hear is a Raiders fan getting viciously slammed on his head

This was absolutely vicious.

It looks like there might have been multiple casualties in Oakland's 33-25 win over the Indianapolis Colts on Saturday. Not only did the Raiders lose start quarterback Derek Carr, but there was one fan in attendance who got his block knocked off.

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While Carr will miss all of the playoffs with a broken fibula, this fan might need to get his head checked. Dude was completely upended and shoved into the stands and still wanted a piece of the perpetrator after the police came to break things up.

[h/t Bro Bible]