The UFC has applied for a boxing licence in Nevada and plans to become heavily involved in the sport, having played a central role in the biggest fight of last year, when Conor McGregor fought Floyd Mayweather Jr in a bout that grossed an estimated $US600 million ($NZ830 million).
The capture of Joshua would immediately make the UFC key players and it is thought the Briton could earn $US50 million ($NZ70 million) per fight if he switched to them, with the prospect of a multi-fight deal taking him to over $US500 million in earnings.
His purse for the fight with Klitschko was around £15 million ($NZ27 million) and just under £10 million ($NZ20 million) for his defence against Carlos Takam last October. The 28-year-old has a year left on his deal with Hearn and is on a mission to unify all the major heavyweight titles, starting with next week's bout against World Boxing Organisation champion Parker. He is then likely to take on American fighter Deontay Wilder in Las Vegas.
Hearn told The Telegraph that he was confident of re-signing the English fighter. But Joshua is a long-term admirer of the UFC and admitted in an interview with Business Insider last week that he could even leave boxing to take on stars such as heavyweight Francis Ngannou, of Cameroon, and former light-heavyweight Jon Jones, both of which he said would be "good scraps".
"A fight is a fight at the end of the day," he told Sky Sports when asked if he would compete in mixed martial arts. "So, yeah, man, I'd do it."
At this stage there is no indication UFC would want Joshua to fight against non-boxers, but White has made no secret of his admiration for a man he said boxing had been "dying waiting for".
"In my opinion, right now, he is the most marketable guy in world boxing," White said of Joshua in the aftermath of McGregor's defeat by Mayweather. Joshua's last three title fights have drawn total crowds of 250,000 and Stipe Miocic, the incumbent UFC heavyweight champion, told The Telegraph that the prospect of a boxing match with Joshua was hugely appealing.
"I'd relish the challenge," he said. "I'd love to fight him, I'm like 100 per cent on that. It's what everyone wants to see, the biggest champions against the biggest champions across the combat sports."
"ZUFFA [the company White has set up to run UFC's boxing division] has a boxing licence now and is looking to go that way. I'd like to face Joshua or anyone who has the titles. I'd love to come to the UK for a stadium fight. I would love it in front of crowds of 80,000-90,000. I'm pretty good at fighting in humongous stadiums against the hometown boy."
Another influential figure in the mixed martial arts industry said they believed a deal could be done. "Dana White going to the event in Cardiff is significant," the source said. "UFC fans would love to see Miocic fight Joshua in a boxing match in the future. It's never been done, but it would be an amazing event. Yes, Mayweather against McGregor was a great event, but two of the great heavyweights going against each other would be just incredible for the fans."
Lennox Lewis is thought to be the highest-earning British boxer of all time, having secured around £84 million during his career. Joshua is almost certain to overtake that figure and could challenge Lewis Hamilton as the highest-grossing Briton in any sport. Floyd Mayweather is the highest-earning boxer, having amassed a fortune of around $1 billion ($NZ1.4 billion) in his illustrious, unbeaten career. It is unlikely Joshua will match that figure, but UFC will hope its offer helps sway his mind.
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