Pacquiao and Mayweather: One More Until the Big One?

Pacquiao doesn't seem to be taking his current opponent for a pushover. Clottey has a 35-3 win-loss record, and 21 of those wins were by knockout. He stands 5 ft. 8 in. tall to Pacquiao's 5 ft. 6 in. and has a strong chin and the muscled body of a boa constrictor. But Pacquiao came into his training camp in great shape, and his sparring at the Wild Card Gym in Hollywood has been crisp and lively; Roach predicts a knockout. Still, it could be a tactically riveting duel, because Clottey likes to lean on the ropes, while Pacquiao will probably try to dive in close, hit him with combinations and then get out of the way of Clottey's uppercuts. (See a profile of Manny Pacquiao in the 2009 TIME 100.)

Mayweather (40-0, 25 KOs) also has a tough opponent. Mosley is a wily 38-year-old who twice defeated Oscar De La Hoya. (Both Mayweather and Mosley have agreed to random blood testing.) Richard Schaefer, CEO of Golden Boy, which is promoting the fight, predicts that HBO will sell 3 million pay-per-view buys to make it the biggest fight in boxing history. It will also be shown in theaters nationwide. (Watch TIME's video "A Free Boxing Lesson with Oscar De La Hoya.)

While waiting to meet in the ring, Pacquiao and Mayweather will compete at the box office. Pacquiao's last several fights have been at Las Vegas' MGM Grand, a 17,000-seat venue, against marquee opponents. His bout against Clottey will be held at Texas Stadium (45,000 seats for the event, and ticket sales have been brisk). But because Clottey was a last-minute replacement for Mayweather with no natural fanbase in the U.S., HBO declined to feature the fight in its popular 24/7 series (it did so for several of Pacquiao's previous matches), and the media tour was shortened to only two cities. Bob Arum, Pacquiao's promoter, chose not to sugarcoat it. "To be frank, we had to overcome disappointment," he says. "People were looking forward to a Pacquiao-Mayweather fight."

Mayweather's match will be staged in the smaller MGM Grand, but it will get the full buildup with a four-episode Mayweather-Mosley 24/7 series on HBO. Mayweather spent last week on a three-city media tour, generating interest in his bout with outlandish theatrics, which included a shoving match with Mosley. Some of the crowd at the Los Angeles event chanted, "Manny! Manny!," but they were drowned out by "Money! Money!," Mayweather's nickname.

Yet both fighters' handlers, as well as Mayweather and Pacquiao themselves, appear unwilling to compromise on the blood-testing issue. Meanwhile, fans descend upon Pacquiao's training gym every day in hopes of catching a glimpse of him. He has had to spend more time than he wanted answering questions about blood testing, steroids and Mayweather — a nemesis who has clearly gotten under his skin. "I have never seen him so angry," says Roach. (See 10 things to do in Las Vegas.)

If a Pacquiao-Mayweather détente can somehow happen, it needs to be soon, while the men are still at their prime. Pacquiao, who is 31, is running for Congress in the Philippines and starting to hint at retirement. Mayweather, 33, has already come back from one retirement. If Pacquiao can beat Clottey and Mayweather is victorious over Mosley, then the fight for the two men's legacies will begin again — at the negotiating table.

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