Tommy Fury and Jake Paul have had to be pulled apart at a weigh-in ahead of their clash in Saudi Arabia on Sunday.
The boxers traded insults and pushes as they squared up hours before their blockbuster fight – billed as “The Truth”.
Their long-standing feud will finally conclude at the Diriyah Arena after two previous scheduled matches had to be cancelled.
Fury, 23, was joined in his corner on stage by half-brother and heavyweight champion, Tyson Fury.
The former Love Island contestant told journalists: “Tomorrow night, his time is up. Jake Paul will no longer be boxing.
“I’m going to put this guy away in four rounds.”
But Paul, 26, has claimed Fury was performing for the cameras.
“He’s acting on stage, getting all hyped up, trying to act like his brother.
“This professional boxer is going down; it’s easy, it’s simple.”
And Paul accused his rival of being nervous ahead of their meeting while insisting he was “ready, calm, cool and collected”.
“This is what I do. He’s shaking up on stage; you can see the nerves running through his system.
“I’m chill,” he added.
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The victor will win a newly-made World Boxing Council Diriyah Belt.
They will also claim a place in the cruiserweight ranking – a decision that has sparked controversy due to Paul’s background as a YouTuber.