Mayweather's celebrated spotless career isn't the only thing going for him, he's also the undisputed money king in all of pro fight sports, a fact even McGregor won't contest.
Figures have shown that McGregor needs a lot of catching up to do. Mayweather is worth $340 million according to Forbes magazine, and is 10 times richer than McGregor. Both fighters are credited for earning some of the biggest purses in the history of their respective disciplines.
Living up to his nickname 'Money,' Mayweather has career earnings of $700 million, with his biggest payday coming in May 2015 when he beat Manny Pacquiao in their much-awaited but lackluster bout in Sin City.
Though the fight failed to live up to the hype, it still was a runaway blockbuster, attracting 4.6 million PPV buys and earning $73 million in gate receipts, $13 million in sponsorship and total gross of $600 million, per Forbes.
While he's nowhere near Mayweather's league, McGregor is credited for anchoring some of the biggest-selling buys in UFC and MMA history.
Forbes revealed McGregor's victory over Nate Diaz in their UFC 202 rematch in August 2016 scored 1.6 million PPV buys, while his knockout of Eddie Alvarez in UFC 205 in New York produced 1.3 million buys. McGregor took home $2 million for each fight. In 2015, McGregor became $15 million richer for his 13-second knockout of Jose Aldo.
Though the disparity is quite glaring, both outspoken stars are fond of spending money and flashing the fruits of their labor.
Mayweather's lavish lifestyle has been well-documented. He owns the Big Boy Mansion, a 22,000-square foot facility and a Las Vegas penthouse worth $1.81 million. A few months ago, burglars stole items worth $150,000 from Big Boy Mansion, a figure which would be described in Pinoy parlance as “Barya lang kay Floyd yun.” Last year, Mayweather also bought a Miami beach home for $7.7 million.
The Big Boy Mansion is also where Mayweather stores his fancy cars. He owns a collection of the rarest Ferrari, Bugatti, Bentley, McLaren, and Lamborgini models, among others. In 2015, Mayweather bought a $400,000 Rolls Royce for his daughter so she could “ride in style.”
For those keeping score, the value of his car collection is $15 million.
The "poorer" McGregor, meanwhile, is also notorious (no pun intended) for living the high life. He used his winnings over Aldo to purchase a $2-million mansion in Dublin, and also has a seven-bedroom, 12,000-square foot home in Las Vegas.
His collection of cars could give Mayweather a run for his money. He owns a Lamborghini Aventi Roadster, a Mercedes-Benz 500, a pair of Rolls Royces, and a new version of the Chevrolet Corvette Stingray, to name a few. Not bad for a guy who briefly retired in 2008 to become a plumber.
Weeks from now, the rich will become richer as these gimmicks-savvy fighters face off in a boxing match that's expected to match or exceed the financial success of both fighters' past topgrossing bouts.
ESPN's Darren Rovell listed the projected financial windfall: $77 million in ticket sales, $475 million in pay-per-view, $22 million in sponsorship, and $2 million in merchandise. Rovell, however, estimated the projected total gross of $600 million, will still be lower than the $625 million raked in from Mayweather's win over Pacquiao.