Former undisputed cruiserweight champion Oleksandr Usyk will push hard for his WBO mandatory crack at the heavyweight title.
Last month, Usyk returned to the ring in his second fight in the heavyweight division - and won a very tough twelve round unanimous decision over veteran Derek Chisora.
The current WBO champion, Anthony Joshua, who also holds the IBF, IBO, WBA titles, will defend his four belts against the IBF's mandatory challenger Kubrat Pulev on December 12th in London.
Usyk's co-promoter, Alexander Krassyuk, says his boxer will not step aside from his mandatory shot.
Joshua, should he win, is going to target a full division unification with WBC champion Tyson Fury.
But unless Usyk steps aside, then Joshua will be forced to vacate his WBO title in order to face Fury.
"Fury may fight any time he feels convenient. Usyk has gone through eight months of hard work getting prepared for Derek Chisora. Now he needs to step back a bit and get some treatment for his body and relaxation for his mind," Krassyuk told Sky Sports.
"Hopefully he will be ready to return in April 2021, and hopefully AJ will be around to comply with WBO mandatory regulations. If not - we will be fighting for the vacant WBO title with a contender appointed by WBO."
Daniel Dubois is ranked at number two with the WBO.
If he beats Olympic silver medal winner Joe Joyce on Saturday, then he could very well face Usyk for the vacant WBO title in 2021 - if Joshua drops the belt.
"I wish we could choose the opponent for the vacant title! Before thinking of Dubois or anyone else we need to know AJ vs Pulev winner and their strategy for the future. But the thing I can make really clear is that we will be pushing hard to put our mandatory position in effect," Krassyuk said.