'Lights out': Jake Paul defeats Andre August with brutal first-round knockout

YouTube star Jake Paul delivered a brutal first-round knockout of Andre August in Orlando, Florida on Saturday.

In his first fight since suffering the only defeat of his unorthodox boxing career in a split decision to Tommy Fury earlier this year, Paul redeemed himself in his cruiserweight bout against August.

With the fight only lasting several minutes, Paul appeared more lively of the pair, peppering August with body shots early.

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August struck Paul in the head with an overhand right hook but the social media personality soon responded — hitting a right uppercut that knocked August out cold.

August was sent crashing to the canvas as referee Christopher Young terminated the eight-round fight.

Marked his victory, Paul waved goodnight to August as he lay dazed and sprawled on the canvas.

"When I walked into Andre's locker room (pre-fight), he looked terrified. That man was done, he was a dead man walking. Jake capitalised and got the first-round knockout," Boxing and MMA journalist Ariel Helwani said.

"The uppercut got it done. His eyes rolled to the back of his head. Lights out."

Jake's brother Logan, who defeated Dillon Danis in a farcical fight in October, stepped into the ring to celebrate.

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Heavily criticised for not taking on professional boxers, this occasion was just the second time that Paul has fought a pro, albeit a 35-year-old veteran with a 10-1 record.

However, with one shot, Paul may have disproved his detractors but drawn more attention to the calibre of his next opponent.

Ahead of the fight, Paul had promised his fans a first-round knockout.

"I said first-round knockout all week," he said afterwards.

"I manifested this. I said I need to bring the old Problem Child back. I've been too nice to these people letting them go into the later rounds. I set up my shot and he went night night".

Paul then made a shooshing motion to the camera, which he explained as "silencing the critics".

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"Everyone who has something to say about me. 'Oh, he can't do this. He can't sell. He's not big. What is he doing fighting this guy, fighting that guy'. Shut the f--- up," Paul said.

"I don't know what I proved tonight. I'm just going to do me. This is all part of the process, the next step to world champion.

"Clearly these guys can't hang with me. He didn't even last two minutes and he's been doing this his entire life. What's next? It's going to be even bigger."

The win takes Paul's professional boxing record to 8-1 with five knockout victories.