Floyd Mayweather Jr. is expected to retire after his next fight. Given Manny Pacquiao's claim about playing through a shoulder injury, will the undefeated champion's next and final fight be Mayweather-Pacquiao II?

The long-awaited Mayweather-Pacquiao fight ended in Mayweather winning by unanimous decision, pushing his career record to 48-0. When Mayweather was asked about his next fight, which he has said would be his last, he answered that he planned to fight again in September. Now the biggest question is which boxer Mayweather will choose to fight in what is expected be his final bout before retirement.

The de facto - and most likely - choice is Pacquiao. Mayweather has a monetary incentive to do it. Saturday's fight may have earned Mayweather around $180 million once the pay-per-view purchases are tallied, and a rematch has the potential to send him away with one last record-breaking payday. Also, who else is there to fight Mayweather? Although the fight Saturday wasn't nearly as exciting as fans had hoped, no other name in boxing is going to give Mayweather's next fight the kind of attention like Pacquiao's would.

Mayweather fought in rematches against Jose Castillo and Marcos Maidana, so fighting an opponent twice wouldn't be a first-time thing. You could also argue the PR machine for Mayweather-Pacquiao II has already started, given Pacquiao's claim after the loss about not being 100 percent healthy for the fight.

"I want a rematch if he wants. I wasn't 100 percent ready for last night because of this shoulder but I don't want to use that complaining that I lost the fight. I'm just accepting the fact that I lost," Paquiao said, according to Bleacher Report.

Yahoo Sports reported after the fight that Pacquiao had suffered a shoulder injury during training and had expected to receive an anti-inflammatory shot prior to the fight. The Nevada Athletic Commission, though, didn't allow for Pacquiao to receive the injection because his injury wasn't listed on a pre-fight report.

"We filled it out but also I'm so disappointed because for the first time in my boxing career, more than 20 years, they hold my vitamins, they hold my water (from) the dressing room," he said. "This is new."

Mayweather's next opponent should be announced in the next couple months.