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LAS VEGAS – The greatest fighters often have the loudest and harshest critics. Jack Johnson was derided as cowardly. Muhammad Ali was portrayed as a lunatic. Fans wanted to organize a "Roycott" of Roy Jones Jr.'s fights because they were so upset by the caliber of his opposition.
It can't come as a shock then, that Floyd Mayweather Jr., perhaps the sport's most physically gifted fighter and perhaps its best, has been inundated by criticism about his courage, his opposition and his style.
Mayweather, who is 40-0 with 25 knockouts, has said he doesn't expect to be truly appreciated until 20 years after his final fight.
Mayweather has the opportunity on Saturday, though, to put a halt to much of the talk when he meets Shane Mosley in the year's most significant bout in a 12-round welterweight match at the MGM Grand Garden Arena.
Mosley is the type of opponent that Mayweather's legion of critics have accused him of dodging – a fast, powerful full-fledged welterweight.
And though Mayweather, a 4-1 favorite, fully expects to win, he doesn't expect the criticism will lessen.
"After I beat Shane Mosley, they'll say he was 38, too old," Mayweather said, waving his hand in disgust. "It's always something."
Mayweather has been a welterweight for 4 1/2 years and has yet to fight opponents like Manny Pacquiao, Miguel Cotto, Paul Williams, Antonio Margarito, Kermit Cintron or Andre Berto, among others.
Freddie Roach, who trains Pacquiao and is a four-time Trainer of the Year, picks Mayweather to win, but insists it's not fair to label him a great fighter, at least not as a welterweight.
Mayweather began as a super featherweight and won world titles at 130, 135, 140, 147 and 154 pounds. Roach, in a line oft-parroted by Mayweather's critics, said Mayweather's caliber of opposition decreased as he moved up in weight.
"He was a very good fighter, maybe even a great fighter, when he was at 130, 135 and maybe even 140," Roach said. "But he's not the same to me since he's been at 147 and . He struggled with Oscar [De La Hoya in 2007 at 154 pounds] and less than a year later, Manny demolished Oscar. He had a hard fight with [Ricky] Hatton and not long after that, Manny beat the [expletive] out of Hatton and knocked him out in two rounds.
"I don't see greatness at 147. He's good, but he's slower, he's easier to hit and he doesn't throw the [volume] of punches he did before."
Despite the criticism, Mayweather has been as boastful as ever and has taken to calling himself the greatest fighter ever. He went so far as to mock Ali for losing to Leon Spinks in Spinks' eighth pro fight, a taunt many in boxing consider almost blasphemous.
Even Mosley, who is so soft-spoken and agreeable that his trainer, Naazim Richardson says, "When you look at him, it's like he wants to sell you car insurance," has taken a few digs at Mayweather's opponents.
Mosley fought Winky Wright, who once fought at light heavyweight, twice, despite being badly outweighed.
"The guys I've fought, they come into the ring at 172," Mosley said. "The guys he's fought, they come in at 145."
Yet, Richardson isn't buying the criticism and is girding Mosley for the roughest fight of his career. Mosley is 46-5 with 39 knockouts and has wins over De La Hoya, Fernando Vargas and Margarito.
Richardson repeatedly calls Mayweather a genius and said that on Saturday, Mosley will be fighting a highly motivated boxing genius. Mayweather has heard the criticism, from fans and media alike, that he shuns the battle, carefully hand-picks his opposition and refuses to engage.
Richardson expects Mayweather to fight with a purpose, to prove a point.
"This fight legitimizes Floyd and Floyd wants to shut you guys up," said Richardson, wagging a finger at a gaggle of reporters. "It wouldn't surprise me if Floyd came out and ran at Shane."
Mayweather has only left the ring with the battle scars of a boxer three times in 40 fights since turning professional in 1996. He was bleeding from the nose and mouth after a 2000 bout with Emanuel Burton (now Augustus). He was bruised and swollen following a 2002 lightweight title win over Jose Luis Castillo, the closest bout of his career and the only one that anyone could make a reasonable argument that he lost.
And his eye was swollen following his 2007 split decision victory over De La Hoya.
Burton and Castillo pressured Mayweather and forced him to the ropes, where he wasn't nearly as effective as he is in the center of the ring. De La Hoya stalked him and, in the first half of the fight, kept a hard jab in Mayweather's face.
Mosley is a quality pressure fighter, but Richardson said it's oversimplifying things to suggest that Mosley will have to cut off the ring, back Mayweather into the corner or pin him on the ropes and then pound away.
"I've watched the DVDs and people constantly refer back to the Castillo fight, but what they don't understand is that Floyd has seen the Castillo fight, too," Richardson said. "How much success have you seen from people with that [against Floyd] since? He's answered those questions about you moving forward.
"Diego Corrales tried to stalk him, tried to walk him down. Oscar tried to stalk him. [Carlos] Baldomir tried to push him back. Ricky Hatton tried to run at him. Gatti stood in front of him. He's answered all those come forward questions. You realize that he understands that formula, so maybe that's not the formula."
Mosley beamed and said he is confident in his plan, but isn't going to reveal it.
Mosley is one of the quickest and fastest welterweights, but Mayweather is faster and quicker. Yet, Mayweather's trainer, Roger Mayweather, said speed and quickness will have little to do with the outcome.
"It's about skills," Roger Mayweather said. "My nephew has the skills."
And he also has the critics.
He wants to win the fight so badly because he wants so desperately to stick it to his critics.
He's probably going to put on his best performance since he knocked Corrales down five times in their 2001 showdown.
That won't shut everyone up, but it will give those critics a lot less ammunition.