TYSON FURY, Francis Ngannou were backed to do "bigger businesses" than Floyd Mayweather's fight against Conor McGregor.
In recent years, the heavyweight champions in boxing and UFC have been calling one another out.
Tyson Fury and Francis Ngannou, UFC champion
They finally met face-to-face when Ngannou, 35, sat at ringside while Fury, 33 knocked out Dillian Howte, 34 at Wembley.
Ngannou was welcomed into the Gypsy King's ring after the Gypsy King announced his retirement.
He maintained that he would still fight in exhibition-style matches while teasing a never before seen boxing match using MMA gloves.
Bob Arum, Fury's US promoter, is open to negotiating a deal for Ngannou. He also predicted mega-success.
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BoxingScene was told by he: "This UFC guy, assuming he can fight, that'll be monumental business.
"They are friends and know each other well. They know what it takes to fight.
"I believe Fury and Ngannou, the UFC heavyweight champion are more successful than Mayweather or McGregor."
McGregor and Mayweather's 2017 cross-over fight sold 4.4 million pay-per-views. There were around PS600m of those sales.
SIGN UP DEALS AND FREE BETS - THE BEST NEW CUSTOMER OFFERINGSWith 4.6m PPVs, Manny Pacquiao's win in 2015 over the 45-year old boxing legend was better than any other.
McGregor's defeat by Mayweather was the first UFC champion to be allowed to compete outside the promotion.
Since then, no such exemption has been granted to active fighters, leading to a contract standoff between Ngannou and Ngannou.
The Cameroonian fighter has finished his UFC contract and is now a champion.
Ngannou warned that if he doesn't have a clause allowing him to face Fury, then he will not extend his contract.
