Conor McGregor claims Floyd Mayweather backtracked on an agreement to fight him in the Octagon.
The pair met in the ring two years ago with the boxing legend winning by 10th-round stoppage.
Mayweather has teased a stint in mixed martial arts since but has remained retired - much to McGregor's frustration.
"Originally the promise was that I fought him on his terms, and he then fought me on my terms," the Irishman told Tony Robbins.
"I haven’t heard from him since. We’ll see what happens. I would love another go in the boxing ring, to see what happens.
"I know he’s not going to come into my game, but I would love to rematch him under boxing rules again and have that knowledge and my sparring partners coming forward with that style and see where we go.
"I believe I would win. Actually, there I go again with that fake humbleness. I know I would win."
McGregor has fought just once since his defeat, losing his UFC lightweight title challenge against Khabib Nurmagomedov.
And he believes he forced Mayweather into a change of style when they clashed.
"Floyd Mayweather is known for his Philly shell defence style of fighting. He has one arm tucked under and another under his chin, he deflects shots with his shoulder," he added.
"He's a back footed fighter, and that’s what I prepared for, because that's what I had seen from him.
"Then, when I went into the fight, I was whooping him in the early rounds. I actually went back to my corner after the first round and said ‘this is easy’.
"Then he had to switch up his style, and you’ve got to respect that, he switched to the Mexican boxing style.
"The Mexican boxing style is where you put your elbows in tight and walk forward with heavy pressure. He never fought like that in his entire career."
