Conor McGregor has been challenged to a $1million bet by Bellator champion Patricio 'Pitbull' Freire.
McGregor is currently negotiating a trilogy fight with Dustin Poirier for this summer after losing their rematch earlier this year.
The third fight is expected to take place in either May or July as the lightweight contenders seek to settle their seven-year rivalry.
But 'Pitbull', who holds the featherweight and lightweight titles in the UFC's rival promotion, wants to put up his own money to prove he is better than the Irishman.
"I'm a big fan of Conor McGregor and I know I can beat him so that's the fight I want," he told MMA Weekly .
His coach Eric Albarracin added: "The original champ-champ versus the reigning champ-champ. The best against the best. Let’s see who comes out on top.
"We got a million dollars saying it’s going to be Patricio Pitbull. Are you willing to take the bet?”
McGregor held the same 145lb and 155lb titles in the UFC as 'Pitbull' does now in Bellator.
But $1m (£720,000) is relative pocket change to the Dubliner at this stage in his career.
He raked in $20m (£15m) for his rematch with Poirier in January and can expect a similar sum from their third fight.
'Pitbull' watched former Bellator rival Michael Chandler record a stunning KO win over Dan Hooker on his UFC debut.
Chandler was himself stopped by 'Pitbull' two years ago, something the Brazilian claims shows the strength in depth in the organisation.
He added: "Michael Chandler is representing Bellator in the UFC. He beat Hooker so easily. That shows how good we are and what we can do there. So it’s not about UFC or PFL, it's about fighters. Everyone deserves that cross-promotion."
'Pitbull' is currently involved in Bellator's featherweight tournament and will defend his title in the semi-final against Emmanuel Sanchez at Bellator 255 on April 2.
