But Usyk (18-0, 13 KOs), 34, of Simferopol, Ukraine, a former undisputed cruiserweight champion, has had some difficulties in adapting to the new weight class, and scraped past Dereck Chisora last time out.
Meanwhile, Joshua (24-1, 22 KOs, 31, of Watford, Hertfordshire, made light work of Kubrat Pulev and is once again the man to beat at the top of the division.
Speaking to Seconds Out, Fury said: “I don’t believe Usyk is a heavyweight for one. I think he’s a pumped-up cruiserweight who struggles with heavyweights.
“In my opinion, Dereck Chisora beat Oleksandr Usyk – he certainly struggled with Dereck Chisora and Joshua is a much bigger, stronger man than Dereck.
“I think he walks straight through Usyk. People are trying to build it up as a scary fight but he didn’t have the power to halt cruiserweights like Mairis Briedis or whoever else he fought.”
But Top Rank CEO Bob Arum, Fury’s co-promoter, believes that an upset could be on the cards as he isn’t entirely convinced that Joshua will be able to cope with Usyk’s technical ability.
“I think Joshua has his hands full with Usyk,” Arum said to iFL TV. I give Usyk a hell of a chance to beat Joshua in that fight.
“Hopefully Tyson comes through and we can do the unification fight in December of this year.”
Unified heavyweight champion Joshua is set to face Usyk at the Tottenham Hotspur Stadium in September, according to Eddie Hearn.
As for Fury, the 32-year-old hasn’t fought since his victory over Deontay Wilder last year.