UFC President Dana White has made it clear that a Floyd Mayweather vs. Conor McGregor rematch would only take place under MMA [mixed martial arts] rules.
Last week, Mayweather has been making social media posts - attempting to get fans to believe that he's going to make his debut in MMA.
In two videos, a barefoot Mayweather is entering an octagon cage, which is widely used by the UFC and other MMA companies, and shaking out a few moves.
Mayweather also posted a photo where he's wearing MMA style gloves with his TMT branding.
Mayweather snapped a two-year retirement back in August of last year, when he fought Conor McGregor, who was making his boxing debut.
After stopping McGregor in the tenth round at the T-Mobile Arena in Las Vegas, the 40 year old Mayweather announced his retirement from the sport - with a perfect record of 50-0 with 27 knockouts.
The event - which many felt would be a mismatch - still generated a fortune, with over 4 million pay-per-view purchases.
Mayweather claimed later on, that the UFC approached him with a multi-fight deal worth hundreds of millions.
Now there are circulating rumors that there are ongoing discussions between Mayweather and the UFC - to stage a McGregor rematch.
If the rematch does happen, White will not allow the second fight to take place in a boxing ring. He says the second fight would have to be in an octagon or it won't happen at all.
“Obviously, the only way making that fight again makes any sense is if he comes over to the Octagon,” White said on UFC Tonight. “We went over and boxed him, the UFC and Conor McGregor. And now it’s time for him to reciprocate and come fight in the Octagon.
“Floyd said leading up to the fight with Conor that he would do both. So we’ll see what happens.”