Unbeaten heavyweights Deontay Wilder and Tyson Fury jettisoned their previously cordial tone in favor of a heated and personal exchange in the final news conference before their highly-anticipated rematch on Sunday (HK time) in Las Vegas.
WBC champion Wilder and Britain's Fury, 31, shoved each other when they took the stage at the MGM Grand before both promised a knockout.
"Wilder is very nervous," said Fury. "I can see his jumper going in and out from the big heart beat pounding out of his chest.
"He's terrified. He's nervous as hell. He doesn't know what to expect, and he's getting knocked out."
Fury added that Wilder would be begging him for a rematch after he is defeated.
The American, with 41 knockouts from 42 wins, responded with laughter at Fury's repeated claim that he will end the fight in the second round. "When I knock you out, go do stand-up comedy. You've got a career there," said Wilder, 34. "You've got pillows for fists and that's why I kept running through you."
The first meeting between the pair in December 2018 ended in a controversial split-decision draw - a result that satisfied neither fighter but left both with their undefeated records intact.
The fight included a vicious right hand from Wilder in the 12th round that sent the towering Fury to the canvas and appeared to end the fight. Miraculously, Fury rose to his feet to reach the final bell.
Fury, who fought twice in Las Vegas last year in raising his win total to 29, wore a jacket of the popular NHL franchise the Vegas Golden Knights and said he was a "bigger star than their homegrown heavyweight" Wilder, who hails from Alabama.
"Is there anything the Gypsy King can't do, including slapping him in the mouth?" he said, referencing his own nickname.
"There's nothing I can't do."
Wilder hit below the belt when he brought up Fury's past struggles with depression, drug use and weight gain.