How the biggest boxing match will bring its fighters millions

The May 2 boxing match between Floyd Mayweather and Manny Pacquiao is expected to be the richest fight in the history of boxing.

After weeks of tense negotiations, the fighters' two promoters finally signed a site contract on Wednesday, allowing tickets to go on sale Thursday, only nine days before the fight.

Ticket sales at the MGM Grand in Las Vegas are expected to hit $74 million, three times the gate record. Pay-per-view revenues from both HBO and Showtime are expected to be around $300 million, double the pay-per-view record set in 2013 when Mayweather fought Canelo Alvarez.

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Along with closed-circuit ticket sales, sponsorships and other revenue, the final fighters' purse may exceed $300 million. Here's how all that money will make its way to the fighters.

The two camps ironed out an agreement over tickets with the help of CBS CEO Leslie Moonves, who also helped set up the original fight agreement in February. Both groups have agreed to have Moonves act as a mediator in any additional disputes. CBS owns Showtime.

The agreement between the two boxers calls for the final purse to be split 60-40 between Mayweather and Pacquiao, except for revenue between $160 and $180 million, which will be split differently, with 51 percent going to the winner of the fight, Bob Arum, Pacquiao's promoter, told The New York Times.

The payday may make Mayweather the highest-paid athlete of 2015, a title that he won with $105 million in earnings for two fights in 2014.