Ohara Davies warned Adam Azim's team that agreeing to their October 19 fight was "the stupidest move you could have made".
Azim defends his unbeaten record against Davies at the Copper Box Arena in London, live on Sky Sports.
Davies is coming off a WBA Interim title defeat to Ismael Barroso. But he has more professional experience than the unbeaten Azim and is known for his heavy punching power.
"It's a lose-lose for you guys," Davies declared. "It's a very hard fight."
Azim, he believes, would get little credit for winning and he added: "If he loses the fight it's a very bad loss.
"You making this fight was the stupidest move you could have made.
"If I hit him he might get knocked out… Who knows?
"I've not sparred him before, I don't know what his chin's like.
"The guy might have a chin made of steel, he might have a chin made of glass. Who knows? We've got to wait until fight night and find out."
To further rile Azim's team, Davies tried to give them a Carl Frampton book and posed for photos in a Carl Frampton T-shirt.
Frampton used to be part of the McGuigan's gym stable and was previously coached by Azim's trainer Shane McGuigan, but split acrimoniously with the team.
Azim has known Davies personally for many years, indeed they held the press conference at the Peacock gym where they first trained together.
Azim himself calmly defused the tension. "We don't need anyone else to talk about. This is a big fight itself," he said.
"I've known Ohara for a long time but when you get into that ring, it's all down to business," he continued.
"We can all be respectful after this. To sell the fight, us two like this talking sells the fight. Our names are big as it is."
Hennessy added to bill
Prospect Fran Hennessy has been added to the show at the Copper Box.
Hennessy picked up her latest victory in June on the undercard of Chris Billam-Smith versus Richard Riakporhe at Selhurst Park. On an emotional night she dedicated that win to the memory of her grandmother, who had recently passed away.
"That was horrible, there were plenty of other things that went wrong in the build-up," Hennessy said.
"I still got in there and did the job. As fighters, whatever we're dealt with we have to get through and fight."
She also promised: "You really haven't seen the best of me yet."
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