Eddie Hearn, promoter for IBF, IBO, WBA, WBO heavyweight champion Anthony Joshua, says his boxer will certainly look for an exception to fight WBC champion Tyson Fury in 2021.

Joshua is scheduled to face the IBF's mandatory challenger Kubrat Pulev on December 12.

But there is also a mandatory challenger under the WBO, Oleksandr Usyk, waiting in the wings.

Usyk will return to action on Saturday night, when he faces Derek Chisora at the SSE Arena in Wembley.

Should Usyk win, he plans to push for his WBO world title fight.

"He has agreed to let AJ versus Kubrat Pulev happen, with regards that the winner fights him next. This statement is still solid," Usyk's co-promoter Alexander Krassyuk told Sky Sports.

"Our plan is: A) beat Derek Chisora, B) push AJ to comply with WBO rules or vacate the title, C) defeat AJ (or any other WBO champion or contender and become the heavyweight champion. Simple and practical."

Should Joshua win, he intends to move forward with finalizing a two-fight agreement to fight Fury in the coming year.

With or without the WBO title, Joshua aims to fight Fury - but he would much rather it be an undisputed fight.

"If Usyk wins, and Joshua beats Pulev, the ruling states that Joshua should fight Usyk next," said Hearn.

"But if Joshua wins he will apply to the WBO and say: 'I would like to fight Fury for the undisputed title'. The WBO can say yes or no. If they say no, we go to Usyk and ask: 'Will you let us [fight Fury] maybe in April'.

"I really want AJ vs Fury to be for the undisputed title. The belts are important to Joshua. He hasn't accumulated these belts and paid the sanctioning fees just to throw them away. He wants to be undisputed. But we also respect Usyk as mandatory challenger. AJ would like to fight Usyk as well. He thinks it's an amazing challenge. He thinks Usyk is a great fighter."