Floyd Mayweather Manny Pacquiao
Eleven-time, five-division world boxing champion Floyd 'Money' Mayweather (L) and eight-division world champion Manny 'Pac-Man' Pacquiao pose at a news conference ahead of their upcoming bout. Reuters

Floyd Mayweather and Manny Pacquiao are finally set to meet in the ring after negotiating on and off for more than five years, but there’s no guarantee the May 2 bout will be the only fight between boxing’s top stars. As the most profitable match in the sport’s history gets closer, there is speculation that a rematch could be in the future.

Three months before the two sides agreed to make the fight official, Pacquiao trainer Freddie Roach said, from his understanding, Mayweather was insisting on getting a rematch, in the case that Pacquiao would be declared the winner. While the contract doesn’t contain a rematch clause, Mayweather-Pacquiao II would make a lot of sense for multiple reasons.

“I know he’s [Mayweather] gonna start quick and we’re gonna start quick also. I think the fans will demand a rematch, and I would love a rematch because I like making money, so it’s pretty good,” Roach told Jenna J of On The Ropes Boxing Radio.

The fight is set to break all kinds of revenue records. It’s expected to gross more than $400 million and sell close to 3 million pay-per-view buys. There are varying reports on how much money the boxers will make, but estimates have Mayweather earning between $120 million and $180 million, while Pacquiao could pull down somewhere between $80 million and $120 million. Even if the rematch were to draw substantially less money than the first fight, it could still make both Mayweather and Pacquiao far more money than they’ve ever gotten for any other bout.

In a recent interview with David Mayo of mlive.com, Pacquiao promoter and Top Rank CEO Bob Arum said that he doesn’t know if Mayweather and Pacquiao will decide to have a rematch. However, Arum has previously indicated that there’s a good chance the world will get to see the best fighters of this generation square off again.

Mayweather-Pacquiao II could also happen regardless of who’s named the winner on May 2. Even if Mayweather keeps his perfect record, a good fight by Pacquiao might increase fans’ interest in the rivalry, making for another enormous payday for the two boxers. After Marcos Maidana lost to Mayweather last year in a fight that was closer than many had expected, Mayweather granted his opponent a rematch, doing so for just the second time in his career.

Any decision that doesn’t go in Mayweather’s favor would seemingly increase the likelihood of a rematch. Having never lost in 47 fights, the undefeated boxer could look for redemption in the result of a loss. It would only make sense for the fighters to meet again if they were to have a draw, considering the amount of hype that surrounds the May 2 fight. Pacquiao’s last draw came against Juan Manuel Marquez in May 2004, though their rematch didn’t come for another four years.

Both Mayweather and Pacquiao will fight again in 2015, regardless of their opponent. Mayweather will likely fight again in September, and he’s indicated it will be the last fight of his career. Pacquiao has a contract with Top Rank through 2016, which calls for him to fight twice a year.