Eddie Hearn has suggested there was an underlying motive to the postponement of Tyson Fury's trilogy fight with Deontay Wilder this month.
The two heavyweights were due to face off in Las Vegas on July 24 for the WBC belt, but the bout has now been delayed.
Shelly Finkel - co-manager of Deontay Wilder - told Planet Sport that the fight had been postponed after Fury tested positive for Covid-19.
"If Fury and his team had taken their vaccinations then there would have been a fight on July 24," Finkel exclusively said.
"All we want is to reschedule and get him in the ring," he added.
"It's looking sometime in October, which is a great shame it's been postponed," Frank Warren told BT Sport.
"Unfortunately, they in the camp and himself got tested positive for COVID," Warren continued.
"There's nothing we can do about it.
"It's the times we live in, so the fight is postponed. Pushed back."
With the world facing at third wave of the highly-infectious Delta variant, that seemed a plausible excuse.
'Disastrous' ticket sales
However, Matchroom promoter Eddie Hearn believes the match up was axed because of "disastrous" ticket sales.
"I just don't feel that a supposed megafight like that, and it's a big fight, just flicks the switch with seven or eight weeks to go and just says 'this is the day we're going'," Hearn told Dazn.
"When you know the business, there's too many issues. So, there was no broadcaster in the UK announced. You know he has a contract with BT? They never announced the fight.
"They sold no tickets. Basically, you could go online and check.
"I don't know whether it was 25% or 30% of the tickets have been sold but that's disastrous.
"There was no hype. This was going to do very, very poor pay per view numbers."
Will AJ fight Fury?
The contest is now expected to take place in October with Top Rank keen to avoid clashing with the likes of Saul 'Canelo' Alvarez on Mexican Independence weekend and Oscar De La Hoya's comeback in September.
The knock on effect of that is that a fight between the winner of Anthony Joshua vs Oleksandr Usyk and Fury vs Wilder will now not happen until 2022.
Joshua vs Fury was being scheduled for this summer in Saudi Arabia, however the British blockbuster was left dead by Wilder's arbitration hearing.
Arum said: "Next time around, if it's Joshua and Tyson Fury, first of all, where should the fight be held?
"There's a big argument that by that time, the pandemic is behind us, we wait until the spring and we do it in Wembley, or one of the big arenas.
"If we wanted to do it in winter, we can do it in Cardiff [Principality Stadium], because 70,000 seats, indoor arena, or it can go to Saudi Arabia."
Joshua instead is facing the Ukrainian Usyk in September with his WBA (Super), IBF, WBO, and IBO heavyweight titles on the line.
The 12-round fight is set to take place on Saturday, September 25 at the Tottenham Hotspur Stadium.