Record breaker! Jorge Masvidal destroys Ben Askren with flying knee in just five seconds at UFC 239

The grudge match between welterweight contenders Jorge Masvidal and Ben Askren didn't last long, as Masvidal produced one of the most spectacular moments ever seen inside the octagon to register the fastest KO in UFC history.

Former Bellator and ONE Championship welterweight champion Askren went into the bout undefeated and looking to position himself for a shot at the UFC welterweight title.

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But Masvidal had other ideas, and he came flying out of his corner to launch a spectacular flying knee at Askren, who was ducking in to shoot for a takedown.

The knee connected flush, knocking out Askren instantly as the T-Mobile Arena reacted with a huge roar for the incredible finish.

By the time referee Jason Herzog had dived in to stop Masvidal from landing additional shots, just five seconds had elapsed. It meant Masvidal not only claimed a spectacular victory to cement his own world title credentials, it also saw him claim the record for the fastest knockout in UFC history.

Such was the impact of the knockout, it took several minutes for doctors to bring Askren back to consciousness, then sit him up on a stool.

But Askren was led away from the cage on his own feet as Masvidal received the acclaim from the Las Vegas crowd.

It was a moment that nobody in the arena will ever forget.