Tyson Fury and Martin Rogan fought out a singing and comedy battle as they met on Tuesday ahead of next month's heavyweight bout in Belfast.
Rogan's impersonation of his fellow Belfastman, the late Frank Carson, probably shaded the comedy exchanges.
Both men predicted they would achieve knockout victories at the Odyssey Arena on 14 April.
"If I can't beat a 40-year-old Martin Rogan, I've no chance of winning a world title," said Fury, 23.
"If he beats me, I'll have to go back to his house and shine his shoes for him.
"By the time of this fight, I'll not have seen my family for 15 weeks because of the hard training I've been putting in.
"I'm in destruction mode. He's in trouble. No man, no army could stop me on 14 April, so Martin Rogan has no chance."
Rogan believes victory could propel him towards a world title shot.
Rogan was a shock winner over Audley Harrison in December 2008 and then beat Matt Skelton to lift the Commonwealth belt before losing that title to Sam Sexton in May 2009.
"I'll be doing so much damage in there against Tyson Fury, it's going to be unreal," said the Belfast man, who has not fought for 18 months.
"This is a great opportunity for me. Tyson Fury is number six in the world rankings at the moment."
Fury vacated his British and Commonwealth heavyweight titles last month after a proposed bout with English champion David Price fell through.
The Manchester native, who has Irish family connections, won the titles by beating Dereck Chisora on points in July 2011.
The Belfast fight could be for the Irish heavyweight title which is currently vacant.