IBF, IBO, WBA, WBO heavyweight champion Anthony Joshua would have no problem with facing one his heroes, Derek Chisora - if War Chisora is able to shock Oleksandr Usyk, according to their mutual promoter Eddie Hearn.

Chisora will face Usyk on May 23 at The O2 in London.

Usyk is the WBO's mandatory challenger to Joshua. If Chisora pulls off the big upset, then he may replace Usyk as the new mandatory contender - although the WBO might go in another direction and order a final eliminator. 

When Joshua was coming up as an amateur, he looked up to Chisora.

They both came out of the same amateur gym and they've been very supportive of each other in the pro ranks.

"They would fight. AJ is a massive admirer of Chisora. Growing up at Finchley, Chisora was a hero to AJ. But they will fight, no problem," Hearn told Sky Sports.

"It doesn't mean, if Chisora beats Usyk, he inherits the mandatory position. But he will become No 1 with the WBO and everybody will say: 'You deserve a shot at the world title'.

Joshua still has to defeat the IBF's mandatory challenger, Kubrat Pulev, on June 20th.

Chisora, if he's on his game, is expected by many to be a real tough test for Usyk.

"Usyk vs Chisora will be a thriller. Usyk is the undisputed cruiserweight champion but this is a different game," Hearn said. "If Chisora gets a hold of him, lean on him, slobber on him, this will be really difficult for Usyk.

"No none will match Usyk's feet or skill but does he punch hard enough in the heavyweight division to keep someone like Chisora, a lion, off him? People will automatically assume Usyk should win but if Chisora gets through the early rounds, and I don't see why he shouldn't, he will be heavy and work Usyk to the body.

"You saw a size difference and a strength difference [in Usyk's fight with Chazz Witherspoon]. He has been working on that. Chisora and [his manager] David Haye fancy this, and they can blow up the division if they win."