Late in the fourth quarter on Friday night, Cal quarterback Zach Maynard took a sack. It was relatively normal on the surface -- Maynard tried to evade oncoming rushers, was grabbed low from behind and went down as two other Washington players cleaned up the mess. It didn't look particularly bad as it happened in real-time but Maynard didn't get up, instead writhing on the ground in pain.

If you don't know exactly what you're looking for, the cause of his injury might not stand out. It might look somewhat normal, like defenders going high-low as often happens in a pileup at the line of scrimmage.

But look a little closer. Watch Danny Shelton, the Washington defensive lineman who goes low on Maynard.

This is a gator roll. It's not unlike the death roll an alligator uses to extinguish its prey. The concept is simple: Grab ahold of the legs and roll hard. The force results in, well ... you saw the video.

Maynard's injury came as a result of an incredibly dirty play. It's not as though Shelton was using the gator roll to take him down. Instead, Maynard was already down -- with two other Washington players on top -- when Shelton followed through with the gator roll.

There's no place for this. Though there's been no word of the extent of Maynard's injury, it looked serious -- he stayed down for quite some time and ended up leaving the field on a cart after being helped to the sideline. And there's no other way to describe the tackle that caused Maynard's injury than dirty.

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