Eddie Hearn, promoter for former two-time heavyweight champion Anthony Joshua, does not believe Tyson Fury will follow through on his promise to retire from boxing - at least not yet.

Last Saturday night, the 33-year-old Fury knocked out mandatory challenger Dillian Whyte in the sixth round, before a record crowd of 94,000 at Wembley Stadium in London.

Afterwards, Fury explained his desire to retire from the sport.

However, there are still a few big money opportunities out there for him - specifically the winner of the upcoming rematch between Oleksandr Usyk and Joshua.

Hearn is not expecting Fury to walk away so soon.

“I don’t really believe anything he says, but he’s also capable of doing anything. Ultimately, it’s on him. If he wants walk away from boxing, good on him. It’s a very tough sport. He’s made a lot of money, he’s won the world heavyweight championship, and if he’s happy doing that, good luck to him. I just feel that his biggest fights are in front of him, the real, career-defining, legacy-defining stuff," Hearn told The MMA Hour.

"There’s a lot of talk at the moment about him being a generational great and better than Lennox Lewis and these fighters of the past, he may be, but ain’t got the resume to prove it yet. But he could do [it]. If he beats AJ, if he beats Usyk, or certainly the winner of that fight, he goes down as an undisputed champion, a Lennox Lewis style, legacy, generational great.

“He’s a really good fighter. I just feel, when you look at resumes — AJ’s got a great resume. Is he a generational great heavyweight? No. But if he can beat Usyk and he can beat Fury, he goes down as an all-time great. That’s what he’s chasing. But it comes back to what do you want? How bad do you want it? Maybe you don’t want it anymore. But I would love to see Fury, who may well be in his prime, fight AJ, fight Usyk. It’s great for boxing. But he’s had a great run and maybe he’s had enough. But I don’t believe him.”

Hearn also doubts a cross-sport showdown will take place between Fury and UFC heavyweight champion Francis Ngannou.

After Fury's win over Whyte, Ngannou entered the ring and the two fighters stood side by side as they discussed the scenario of scrapping in the near future.

The UFC claims to have some contractual claims to Ngannou, who feels he's a free agent.

UFC President Dana White, and Fury's co-promoter Bob Arum of Top Rank, have been feuding for years.

Because of that feud, and other reasons, Hearn doesn't see the cross-over bout taking place.

“It’s a big fight. I actually don’t [think it happens.] I don’t know the contractual situation,” Hearn said. “I think Tyson Fury’s up with ESPN or about to be and Ngannou’s up with the UFC, maybe Dana comes in and does it himself, or maybe I do it with Dana. I don’t know...

“Big fight. Big fight. But it’s the contracts, I can’t imagine Dana doing a fight with Bob Arum, how long the contracts are, is Ngannou gonna re-sign? The Ngannou situation, I would be very surprised if Ngannou left the UFC without Dana White having some kind of involvement or control.”