Dillian Whyte laughed off a knockout threat from 'Prince' Charles Martin and says the former IBF world champion "embarrassed himself" in defeat to Anthony Joshua.
Britain's WBC 'interim champion' received a new challenge from Martin, who vowed to inflict a crushing defeat if Whyte was willing to face him in America.
Martin's reign as IBF champion was ended by a second-round loss to Joshua in 2016, a fight he told Sky Sports was "the biggest mistake of my life".
But Whyte told Sky Sports: "It sounds like Charles Martin is up to his old tricks and is desperate for a payday to keep him going. Nothing he says worries me in the slightest. Ravings of a deluded fool.
"Actually, I think even the real Prince Charles would knock him out.
"Look, he's an okay fighter, he's better than the one that showed up against Joshua, but he's not a guy where you sit there and think, 'wow, Charles Martin wants to fight me'. He's a useless bum really.
"Now I'm in a good position and now I've got my title, and now I'm probably the biggest money fight he can get.
"Listen, this is heavyweight boxing. If he puts himself in a good position and it makes sense, but if I fight him and knock him out in a few rounds, people are going to say, 'Well Joshua knocked him out in two rounds'.
"He's embarrassed himself, so it makes it hard to make a case to fight him, because if you beat him in three rounds or four rounds, people are going to say, 'Well Joshua beat him in two rounds'. Same way if I beat him in a round. 'Well, he never recovered from the beating Joshua gave him'.
"He's damaged goods just like that other waste of space Dominic Breazeale."
Whyte confirmed that Jermaine Franklin, an unbeaten contender, is a potential opponent for his next fight, which is expected to be scheduled in the US.
"Jermaine Franklin is in the running," Whyte told Sky Sports. "There are a few other guys in the running as well, so we're just waiting to see what is going on.
"The plan is to have the biggest and the best fights I can wherever they are. I've been chasing the big fights for a long time.
"I'm willing to fight anyone, but it's been hard getting the challenges I want. I've been trying to fight Wilder for 600 years. I've been trying to fight Tyson Fury, I've been trying to fight Joshua, I've been trying to fight Andy Ruiz, I've been trying to fight Luis Ortiz.
"I've been trying to fight all of these guys but none of them wants to fight, so I have to take the next available dangerous contenders down the list. If it's America, then let's go!"