Anthony Joshua has been dealt a major blow in his pursuit of becoming undisputed heavyweight champion of the world.

The biggest fight in the history of British boxing is yet to get going, but Eddie Hearn has cast doubt on Rob McCracken being in Joshua's corner against Tyson Fury. 

Hearn has earmarked July 24 as the date for Joshua's unification fight with Fury, but this will clash with McCracken’s Olympic duties.

McCracken, 52, competed as a professional boxer from 1991 to 2001 and reigned as the Commonwealth middleweight champion from 1995 to 1997. 

But the demands of juggling his performance director's job with being Joshua's trainer may finally prove to be too much.

It will be a crushing blow for the Olympic gold medallist, who has already expressed his admiration for his head coach.  

"Rob is a gaffer - I look at him like Sir Alex Ferguson. Great manager, great trainer, great experience," Joshua said to Sky Sports. "Me and Rob conquered the international stage as amateurs. Then I turned pro and me and Rob conquered the world."

Hearn acknowledged that the situation is far from ideal for all the parties involved.

But the Matchroom boss is adamant that it is very much business as usual for the WBA, WBO and IBF heavyweight champion.

"I know Rob takes his position very seriously," Hearn said. “He loves the job and the kids so it’s not ideal but we can’t move it a couple of weeks either side. Someone is spending a lot of money so we have to go whenever they say."

"We haven’t finalised an exact date, July 24 is the rough date but it may leak into early August but no later than that. It’s impossible to schedule anything without clashing with something," he added. "I know AJ and Rob have been talking accordingly so I am sure they will work it out."

Read more: Anthony Joshua vs Tyson Fury: Date, Tickets, Venue, Odds, Stats And Everything You Need To Know