'That was nasty': Exploding lip KO shocks UFC world

Alistair Overeem has suffered one of the most disgusting lip injuries ever seen in the UFC.

The gruesome incident in his UFC defeat to Jairzinho Rozenstruik has left viewers more than a little squeamish.

The record books will show Rozenstruik finished Overeem with just four seconds left in the fifth and final round of their bout.

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However, the fight will be long be remembered for the savage way it ended for the British fighter after a massive hit from Rozenstruik.

Overeem was seemingly well in front on the scorecards going into the final round of the bout.

However, with a matter of seconds remaining he was caught flush across the jaw by a vicious right hand from Rozenstruik.

The force of the blow caused Overeem's lip to explode, leaving him with a sickening gash across his mouth.

The referee leapt in to stop the fight, handing Rozenstruik a stunningly unlikely victory.

Replays painted a brutal picture of the injury suffered by Overeem as viewers reacted in horror to what they'd witnessed.

The television broadcast team reported after the bout that Overeem was ahead on all ringside judges’ scorecards four rounds to none, heading into the fifth round.

Nevertheless, Rozenstruik's win is the UFC rookie’s fourth win of 2019 and he improves his MMA record to a perfect 10-0.

Overeem’s record dips to 45-18-1. Both men have long pro kickboxing records on top of their MMA marks.

Rozenstruik began the fight refusing to shake hands with Overeem and afterward explained that he had felt disrespected by “The Demolition Man.”

“You say I’m not [on] your level then I think you’re missing something,” he said, post-fight.

“It was a hard fight. The guy’s a really smart guy … but still, I knocked him out … [I] don’t need too much. One shot, one kill.”

With Yahoo Sports US