Dillian Whyte attempted to antagonise Anthony Joshua ahead of their London bout on Saturday, calling the Olympic champion a robot and a fraud and reminding him of a criminal conviction for drug possession as their pre-fight media conference descended into an argument.
The London heavyweights meet for the British and Commonwealth titles at the O2, with the simmering tensions between the pair all too apparent on Thursday.
Whyte goaded Joshua as the pair renewed hostilities following a October 2009 amateur bout which Whyte won.
"I don't need to be on lottery (funding) to be loaded on steroids," said Whyte of the London 2012 gold medallist, who in 2011 pleaded guilty to possessing a class B drug.
Joshua did not respond to the steroids allegation, but kept his calm and his retort was swift.
"You got a two-year ban," he said.
That was a reference to Whyte serving a suspension for testing positive for controlled substance methylhexaneamine following a fight in 2012.
Whyte suggested Joshua's public persona does not match with reality.
He said: "You are fraud, you fake. You are not this nice guy, you are scum.
"After the fight on December 12 that not the end of it. I'm going to find you and we are going to have a street brawl."
Joshua attempted to defuse the situation, calling on Whyte to "compose" himself.
Joshua is confident of extending his record of wins by knockout in all 14 of his professional fights against Whyte, who is 16-0, with 13 KOs.
Joshua said: "It's just another day in the office, really.
"I don't know much about his ambition, his ability, where he is now. He talks a good game and it would just be good if he backs it up.
"No disrespect to any fighter. A real test would be someone like the Klitschkos, (Tyson) Fury, the (David) Hayes of this world.
"Me and Dillian are prospects coming up. I'm just excited to push on, really, just do my job.
"This is what I train for. It's a routine stop. I've trained for a 12-round fight, but I think it will go three or four rounds."
Joshua attempted to explain his defeat in their previous meeting, when Whyte was fighting for the first time after switching from kick boxing.
"When I first started boxing I thought I was the man. I knocked out my first two opponents," Joshua added.
"Dillian was very experienced. He knocked me down. My heart had the courage to pick myself up and fight until the final bell.
"It made me realise I need to step my game up if I wanted to fight guys at that level."
Whyte is confident of a repeat success.
"I can't wait to smash this robot to pieces. Simple as that," he said.