Their decade-long partnership is peaking with the richest paycheck in sports history.
But where will boxing's top pound-for-pound fighter, Floyd Mayweather Jr., and the most powerful man in the sport, his manager Al Haymon, go from here?
Mayweather (47-0) says his fight Saturday against Manny Pacquiao will be his next-to-last fight, and his career will close in September — either in a lucrative rematch against Pacquiao or a farewell fight versus a lesser foe.
Haymon, a Harvard-educated economics graduate, doesn't speak to reporters. At the Mayweather-Pacquiao news conference Wednesday, Haymon briefly peeked out from behind a curtain, then disappeared again, reinforcing his reputation as boxing's Wizard of Oz.
After Mayweather retires, Haymon will be busy with his new Premier Boxing Champions circuit, which debuted this year on NBC and later broadcast or announced fight cards for CBS, ABC/ESPN, Showtime and Spike TV. But it's not a given that Mayweather and his company, Mayweather Promotions, will be included in PBC's bold push. Other than Mayweather, his company claims just one other world champion, little-known super-middleweight Badou Jack.
Among those watching how the Mayweather-Haymon partnership will proceed are Pacquiao's promoter, Bob Arum, who formerly promoted Mayweather. "Just see how Haymon treats [Mayweather] after he finishes fighting," said Arum, whose disdain for the manager is well-known.
Haymon helped Mayweather pay $750,000 in 2006 to buy out his Arum contract. It's been a golden brick road for Mayweather ever since.
In 2007, Mayweather broke out of Oscar De La Hoya's shadow, beating the "Golden Boy" in the most-watched pay-per-view fight in history — though Saturday's fight will top it. He proceeded to multimillion-dollar paydays, including a six-fight deal with Showtime in 2013 that has paid Mayweather in excess of $30 million per bout.
"The guy is brilliant, a genius," Mayweather said, recounting a series of conversations in which he quoted Haymon.
"When you wanted the big-boy mansion, did we get it built? When you wanted to be the highest-paid boxer … the highest-paid athlete … to buy the Bugatti … the house in L.A. … in Miami, the 14-passenger private jet … did we make it happen?
"Yes," Mayweather answered, as he anticipates earning more than $200 million for Saturday's bout.
Yet, as Mayweather talks of longing for retirement and boarding his jet to watch any NBA game he wants, Haymon is bolstering his empire without the boxer.
Mayweather believes he'll remain tightly connected to Haymon. "We have an unbreakable bond," Mayweather said.
In positioning for PBC's debut, Haymon stockpiled a slew of talented boxers to boost an already impressive stable. Heavyweight champion Deontay Wilder, light-heavyweight champion Adonis Stevenson, unbeaten welterweights Danny Garcia and Keith Thurman and unbeaten super-bantamweight champion Leo Santa Cruz are managed by Haymon.
It took a nasty split with Oscar De La Hoya's Golden Boy Promotions to secure some of those boxers. De La Hoya sued his company's former chief executive Richard Schaefer for making fight deals with Haymon in a way that De La Hoya believed had compromised Golden Boy's grip on several fighters. In a settlement, Schaefer agreed to stay out of boxing promotion until August.
Haymon began rolling out the PBC fights in March through time-buy arrangements with the networks — in which Haymon buys the television time and sells the ads himself. PBC has thus far produced high-quality shows in its bid to attract a new, wider audience.
"Tremendous thing for the sport," Espinoza said.
Rather than let Mayweather Promotions promote the PBC bouts, however, Haymon has aligned with others, like Goossen Promotions in the Southland and promoter Lou DiBella in New York.
DiBella said Haymon's model is ambitious and exactly what the sport needs. "One [Mayweather-Pacquiao] fight like this can't save the sport, but it can leapfrog the industry back into greater significance," DiBella said.
Yet even now there is controversy over Haymon's role.
This week, the Assn. of Boxing Commissions urged U.S. Atty. Gen. Loretta Lynch to investigate Haymon in connection with the Muhammad Ali Act that prohibits a manager from doubling as a promoter.
"I don't think he's doing anything wrong," DiBella said. "The Ali Act is meant to protect fighters. Do you think any of these fighters in the PBC aren't getting the best money? These fighters have more opportunities, platforms and venues than ever."
Haymon's hold on fighters is powerful.
Santa Cruz is so appreciative of Haymon's guidance that he named his young son Al. Santa Cruz, 26, will fight little-known Jose Cayetano on the Mayweather-Pacquiao undercard. "Al Haymon knows what he's doing, he's always there to take care of me," said Santa Cruz.
Last week, Haymon was named manager of the year at the Boxing Writers Assn. of America dinner, and though Haymon wasn't present, someone read his speech.
"It's the boxers who deserve all the credit for this," Haymon wrote. "The boxers … deserve the lion's share of the financial rewards and they should be placed on the biggest platform before the largest audience possible to display their talents."
Mayweather is the monument to that philosophy.
"In one garage, I have four cars worth $10 million," Mayweather said. "People say I took on the villain role because I am one. No, I had a business plan. I was brilliant, I was smart. … And here we are in the fight of the century."