Floyd Mayweather
Floyd Mayweather holds four titles after being stripped of his WBO welterweight championship. Getty

Any small chance that Floyd Mayweather would take on Kell Brook or Timothy Bradley in September might have ended on Monday. The WBO voted to strip Mayweather of his welterweight belt, ending the possibility of a world title unification fight in the latter part of 2015.

Mayweather won the WBO welterweight title when he beat Manny Pacquiao on May 2, adding a third belt at 147 pounds to his collection. Both Brook and Bradley currently hold a title in the same weight class, as Mayweather searches for his next opponent. But Mayweather never paid the WBO a $200,000 sanctioning fee by the July 3 deadline, and he’s been forced to relinquish the belt.

It’s not a surprise that Mayweather is no longer the WBO champ, considering the boxer said he would vacate his titles after defeating Pacquiao. But he had yet to do so, and the WBO was forced to take action.

After beating Pacquiao, Mayweather held welterweight titles for the WBO, WBC and WBA. Brook has been the IBF welterweight champ since Aug, 16, 2014, and he’s been holding out hope to get his chance at the sport’s top pound-for-pound fighter. But Brook and his promoter, Eddie Hearn, realized that the fight would likely never come to pass, and Monday’s news confirmed that fact even more.

"We would love to make the Mayweather fight for Kell on September 12 and we are in the hat because Kell's world champion and if Mayweather wants to become undisputed champion with all the belts he has to take that fight,” Hearn said in late June.

"I don't think we will get it and others have been mentioned. Kell Brook is more creditable than the names that have been mentioned and like I said Mayweather could have the chance of unifying the division, but I don't think it will happen.”

The undefeated Brook is one of the most formidable opponents that Mayweather could potentially face, and he’s even been called out by Keith Thurman to take on the Brit. But Andre Berto appears to be the favorite to take on Mayweather in September, and the undefeated boxer has also said he’ll consider fighting Karim Mayfield.

Now that Mayweather is no longer the WBO welterweight champ, Bradley is the only one in possession of the belt. Because Mayweather made it known that he would vacate all of his titles after defeating Pacquiao, the WBO deemed Bradley’s welterweight fight with Jessie Vargas on June 27 a title fight. The “interim title” was officially on the line, because Mayweather never relinquished his titles.

After Bradley topped Vargas, a future meeting with Mayweather made sense. Bradley has beaten some of the best fighters of his era, defeating both Pacquiao and Juan Manuel Marquez in the last three years. With Bradley-Vargas II not likely to happen, Top Rank CEO and Bradley’s promoter, Bob Arum, has said he wants the interim champ to challenge Mayweather.

"If Mayweather is looking around for an opponent, the guy capable of giving him the best fight, who is available, is Bradley. Many people would agree with that," Arum said. "I've let it be known, and now it's Mayweather's decision. So now I'm waiting for a call from his people or not. I'm not waiting with baited breath by my phone, but they know where to call me.

"If they call me, I will try to set up the fight. We showed from Mayweather-[Manny] Pacquiao fight things could be worked out."

But now that Mayweather has made at least $220 million in his win over Pacquiao, the chances of him doing business with Arum again are slim-to-none. Instead, Bradley could take on Sadam Ali in his next fight.

Mayweather Promotions CEO Leonard Ellerbe called the WBO’s ruling a “complete disgrace.” Mayweather can appeal the decision, but there’s little reason for him to do so if he plans to retire after his next fight, as he claims.

Mayweather held five titles before Monday, including two at 154 pounds. The WBA and WBC have allowed Mayweather to keep his welterweight titles, despite holding belts in other weight classes. Mayweather won his two light middleweight championships when he beat Canelo Alvarez and Marcos Maidana in September 2013 and May 2014, respectively.