The former unified heavyweight champion locked horns with the MMA superstar in a lucrative crossover clash in Saudi Arabia early on Sunday morning.

Joshua was razor sharp from the get-go, knocking down the former UFC champ in the first-round with a picture-perfect straight right hand.

AJ floored with the Cameroonian clubber with a huge right hand and left hook.

And he shut his lights out with a hellacious overhand right a few seconds later.

Ngannou lay on the canvas before being helped to his feet.

And the PFL pounder was subsequently given oxygen after being helped to his corner.

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