Anthony Joshua “probably thinks” a fight against British heavyweight rival Tyson Fury “will never happen”, according to his promoter, Eddie Hearn.
It fell through after an arbitration hearing ruled Fury must first face American Deontay Wilder.
“AJ never felt they wanted the fight, he never felt like Fury wanted it,” said Hearn.
“I think AJ, in his head, probably thinks the fight will never happen. I would like to be more hopeful and I think it will happen.”
WBC champion Fury, 32, will now fight 35-year-old Wilder for a third time when they meet on 24 July.
Joshua, meanwhile, holds the IBF, WBA and WBO titles and has been ordered to defend the latter of those against mandatory challenger Oleksandr Usyk.
“If AJ knocks out Usyk and Fury knocks out Wilder then in four months we are talking about an even bigger fight,” added Hearn.
“One could lose or look bad but I do get the feeling if they both win then the fight is huge. I am hoping it works out for the best.”
Talks between the Joshua, 31, and Usyk camps are continuing, with their fight expected to take place on either 18 or 25 September at the Tottenham Hotspur Stadium.
Ukraine’s Usyk, 34, is a former undisputed world cruiserweight champion and has 18 wins from 18 bouts.
“AJ knows how good Usyk is but he wants to do a job on him because he also knows people are unsure about him winning the fight and I think he likes that,” said Hearn.
“He has done four weeks of southpaw sparring up in Sheffield and he is gearing himself up for a big fight. We just hope that everywhere is open because we want to do 60-70,000 at Spurs.”