Dillian Whyte says Oleksandr Usyk is not a "true heavyweight contender" and believes Anthony Joshua knows he would receive "major damage" in a heavyweight rematch.
Joshua has been ordered to face Usyk, his WBO mandatory challenger, after plans collapsed for an undisputed world title fight against Tyson Fury.
But Whyte has raised doubts about whether Usyk can pose a serious threat to the WBA, WBO and IBF champion.
Anthony Joshua has been ordered by the WBO to defend his championship against mandatory challenger Oleksandr Usyk in his next fight— Sky Sports Boxing (@SkySportsBoxing) May 22, 2021
"It's a dead fight. Usyk hasn't looked good," Whyte told Sky Sports.
"Who has he fought at heavyweight? Chazz Witherspoon, Derek Chisora. He looked terrible in the fights. He has no punch power.
"Okay, he's got good movement, but it's not nice movement. At cruiserweight his movement was nice, but at heavyweight, his movement is not nice. It's just so negative.
"The Derek Chisora fight, I watched the first six rounds and when Derek tired, I was like, this is rubbish. Derek was out on his feet and he couldn't even stop him. He was punching him clean and Derek was walking through.
"Usyk is not a true heavyweight contender.
"There are only a few fighters special enough to replicate what they did [at cruiserweight]. David Haye is a good fighter. He didn't replicate what he did at cruiserweight at heavyweight. Enzo Maccarinelli was the same.
"Evander Holyfield stands out. Evander Holyfield did it. Dwight Muhammad Qawi and those guys, moved up and did well at heavyweight, but Usyk hasn't got the style.
"Now he is 105 kilos, he is going to struggle to carry that weight around the ring, and he isn't one ounce stronger."
Whyte regained the WBC 'interim' title with a fourth-round knockout victory over Alexander Povetkin in their 'Rumble On The Rock' rematch in Gibraltar in March.
The Brixton man says Joshua is fully aware that he will receive another punishing encounter if they share the ring again.
"These guys know," said Whyte. "You can say what you want about me, but there are two things that they cannot deny. I always come to fight and anyone that fights me, you will know that you've been in a fight, regardless, win, lose or draw.
"The two fights I lost, the guys took major damage.
"Anthony Joshua almost got knocked out when I fought him. If you watch the clips back you hear him saying, 'If I took one more body shot from him, I would have folded in half'.
"These guys know regardless, win, lose or draw. I come to give work."