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Israel Adesanya finally beats Alex Pereira with nasty KO (Video)

Of all the knockouts on this list, this one may have the biggest backstory to it.

Israel Adesanya was looking for revenge once again when he took on longtime rival Alex Pereira in the main event of UFC 287. The two fought twice in kickboxing, with Periera winning both times — winning by decision in April 2016 and delivering such a vicious KO of Adesanya that he was stretchered out of the ring in March 2017.

When they met for the first time in the Octagon at UFC 281 in November 2022, Adesanya had a better performance and looked to be on his way to a decision victory. But Pereira rocked him and finished Adesanya in the fifth round to capture the UFC middleweight championship.

When the fight for UFC 287 was made, there were plenty of concerns if Adesanya would be able to beat the man considered his "boogeyman." And things didn't look great for "The Last Stylebender" early on, as he landed plenty of strong combinations and damaging shots on Adesanya.

During the second round, Pereira threw combinations on Adesanya, who was pressed against the cage. But after blocking the shots rope-a-dope style, Adesanya landed a powerful combination that knocked Pereira out cold. Adesanya celebrated, finally conquering his demons and re-capturing the UFC middleweight championship.

Adesanya did not hold the title for long, dropping it to Sean Strickland at UFC 293, but it won't take away from the memorable finish that he had on this night.