He's also one without an opponent for his next fight. And without some unforeseen miracle, that next opponent will not be the world's choice, Manny Pacquiao.
Nevertheless, it's almost guaranteed that Mayweather won't fight until sometime in 2013, meaning that almost all of the non-Pacquiao fighters are seemingly in play. When looking at those guys, a few opponents stand out as ones that would not only satisfy the boxing masses but would also create plenty of intrigue for casual fans as well.
With that in mind, here is a look at the best possible opponents both from an in-ring and outside-the-ring sense.
Saul "Canelo" Alvarez (41-0-1, 30 KO)
Though he's just 22 years old and relatively unproven, Alvarez should be Mayweather's choice if he actually wants to produce the best fight.
Many will point to his victory over Shane Mosely in May as the first sign that Alvarez was ready, but it was his utter evisceration of Josesito Lopez that sealed it for me. Facing an overmatched opponent, Alvarez refused to box down to his level of competition and took care of business.
All that aside, the most intriguing aspect of a potential fight with Alvarez would be an almost perfect meshing of styles. Canelo is aggressive (at times wildly so) and is one of the hardest young punchers in boxing.
Meanwhile, Mayweather has built his entire empire on other fighters' inability to mark up Pretty Boy Floyd's face. He's a defensive technician who is at his best when he's stripping the opponent of his best tool.
Essentially, it's the very light version of why everyone and their great-grandmother want to see Mayweather fight Pacquiao.
Yuriorkis Gamboa (21-0-0, 16 KO)
If Mayweather's beef with 50 Cent is real and not just some inane way to keep Money's name in the headlines, a fight with Gamboa could lead to one of the most captivating pre-fight stages in boxing history.
Two former BFFs with nonexistent filters yapping at each other back and forth, all while renewing a heated rivalry between 50 Cent and Rick Ross in the process? Excuse me while I call my cable provider and order HBO just to watch 24/7.
As for the actual match, well, Mayweather would almost certainly flatten Gamboa. Though he's a strong fighter at 126 pounds, Gamboa would not be able to keep up with Money after gaining the weight necessary to fight in whichever division that the two would hypothetically agree on.
Nonetheless, if Mayweather wants a warm-up bout that's a relative breeze and wants to get back at his former business partner, destroying Gamboa would be an entertaining way to go about it.
Timothy Bradley (29-0-0, 11 KO)
While Gamboa would provide plenty of intrigue outside the ring, Mayweather should choose Bradley for the ultimate package fight.
Obviously, the main draw of Bradley is his controversial split-decision victory over Pacquiao in June. Although the fight is widely regarded as a robbery, that fight alone made Bradley one of a select few household names in boxing.
The controversy surrounding that decision and Bradley's ties to Pacquiao would help satiate the masses for a big fight while actually giving Mayweather a challenging fight.
Bradley is 29 years old, undefeated and in his boxing prime. He's been a dominant force in the light-welterweight and welterweight division for the entirety of his career and was actually one of the more underrated fighters in the world.
Mayweather would still be a heavy favorite, but fighting Bradley is the choice that would intrigue most boxing fans.