• Saul "Canelo" Alvarez beat Sergey Kovalev in Las Vegas on Saturday.
  • The Mexican fighter won Kovalev's WBO light heavyweight after knocking the Russian out in the 11th round.
  • Canelo is now a simultaneous champion at middleweight, super middleweight, and light heavyweight.
  • Watch footage of Canelo's finish below.
  • Visit Business Insider's homepage for more stories.

Saul "Canelo" Alvarez hit Sergey Kovalev with a knockout punch so hard the Russian collapsed through the ropes, could barely get up, and was told by the referee that he could not continue.

Canelo, the reigning middleweight and super middleweight boxing world champion, ventured into the light heavyweight division to challenge Kovalev for his WBO title.

Just 10 weeks removed from his 11th round stoppage over the British fighter Anthony Yarde in late August, Kovalev was straight back into action Saturday at the MGM Grand Garden Arena in Las Vegas, Nevada, giving as good as he gets against Canelo for much of the fight.

Kovalev boxed so well that Canelo had to switch strategies, from targeting the body with crisp punching, to attacking the head with meticulous shots.

Then, in the 11th round while the judges' scorecards at ringside were fairly even, Canelo scored his finishing blows.

With his guard up to block any Kovalev shots, Canelo unleashed a sense-separating left hook that staggered Kovalev. Capitalizing on his dizzy opponent, the Mexican thumped his opponent with a thudding straight right, sending Kovalev crashing to the canvas.

It was over.

Watch it right here:

With victory, Canelo sees his record move to 54 wins (37 by knockout) against two draws and just one loss, which he suffered in 2013 when he dropped a decision to Floyd Mayweather.

It is unclear who he will fight next or which world title he will defend as he currently holds belts in three weight classes.

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This article was written by Alan Dawson from Business Insider and was legally licensed through the NewsCred publisher network. Please direct all licensing questions to legal@newscred.com.

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