Bob Arum, Pacquiao’s promoter at Top Rank Boxing, was incensed. He said he was a victim of “PosterGate.” He called out Mayweather’s promotional team—Oscar De La Hoya’s Golden Boy Promotions—for having a “thug mentality” and went out of his way to criticize his host.

Given that Mayweather is the biggest name and draw in boxing, the MGM’s promotional blitz might not seem out of the ordinary. But the MGM's effort added another strange chapter to an already strange rivalry that’s been harmful to the sport of boxing.

The rift has several causes, including a dislike between Arum and De La Hoya. The two men have split up the boxing world. In the Top Rank corner: Tecate, HBO, Pacquiao and a solid stable of fighters. On the Golden Boy side: Corona, Showtime, Mayweather, and a solid stable of fighters. Unfortunately for boxing fans, the two promoters won’t allow their fighters to battle each other. The rival networks and beer makers have been forced to align themselves with the promoters, and the fighters are mostly powerless. The current situation allows the promoters to control their own fiefdom, and as a result, competition is less fierce.

But the Golden Boy-Top Rank rivalry isn’t only affecting how fights are made. Some fighters are actually running out of worthy opponents. For example, Golden Boy fighter Canelo Alvarez has already fought Mayweather. But he won’t be able to fight Pacquiao or Bradley, similarly elite boxers, because they are Top Rank Fighters. As the promotional rivalry goes on and becomes more bitter, more fighters will find their options—and their marketability—limited.

And, of course, this feud has implications for the two best fighters in the world, who are both welterweights. The undefeated Mayweather has gone through all of the best welterweights in the world, and Pacquiao is the painfully obvious choice as an opponent. They have never fought each other. They are both still near the top of their games. So it seems obvious that they should fight. The feud between their promotional firms ensures that they can’t, however—and that other promising matchups can’t happen, either. And this is actually hurting the sport.

Just look at the events that led to Pacquiao’s latest encounter with Bradley. Two years ago, Pacquiao fought Bradley. Most pundits believed that Pacquiao won the fight easily. (I sat ringside and scored it 9 rounds for Pacquiao, 3 rounds for Bradley.) It was a blowout win, and no fight fan wanted to see the two men face each other again. But the judges gave the win to Bradley. There was outrage. Pacquiao, 35, then fought Juan Manuel Marquez for the fourth time (and lost in a devastating knockout) and then dominated Brandon Rios. But who could he fight next? There was no one in the Top Rank stable that made sense. So Top Rank concocted another fight with Bradley.