Las Vegas will host the big fight between Mayweather and McGregor on August 26 which is worth $500million.
Mayweather has won every single one of his 49 bouts, winning 26 by KOs, whereas The Notorious McGregor went unbeaten in UFC for six years before losing to rival Nate Diaz in March 2016.
The American is on a minimum certainty of $100million (£78m), plus the upside on high sales by Showtime, the major US cable network.
Irishman McGregor’s share of the bounty is thought to be in the region of $80m (£62m) but a percentage of that will go to the UFC, his paymasters in his customary field of action mixed martial arts.
McGregor who is used to kicking in a fight, will face a lawsuit if he tries to kick Mayweather on game day.
“That [kicking] will not happen; it’s in the contract. This is a boxing match under the Nevada commission under the rules of boxing.
“We talk about a guy of Floyd Mayweather’s value in the sport – the lawsuit if that ever happened…
“Conor loves money and he would lose a lot of money if that happened,” UFC president Dana White said.
According to oddschecker.com. Mayweather is currently odds on favourite to win the fight at 2/17 with McGregor a 7/1 outsider.