Pacquiao opened the decade as a 21-year-old ex-WBC flyweight champion who owned a 27-2 record and had fought just three times outside his native Philippines, his final pre-2000s excursion resulting in a third-round knockout loss to Medgoen Sengsurat in Thailand in 1999. Today, Pacquiao (50-3-2 with 38 KOs overall; 23-1-2 with 20 KOs this decade) owns seven world titles in seven weight classes, and is quite possibly the finest fighter in the world pound-for-pound. With an improbable combination of speed and power, he's an electrifying presence in the ring, a relentless attacker and a master of distance who comes at opponents from surprising angles while still maintaining tremendous leverage and balance. He also fights with an urgency and a joy unseen since the young Roberto Duran. Best of all, Pacquiao, 31, may not even have peaked yet; under trainer Freddie Roach, he just keeps getting better.
Floyd Mayweather Jr.
The flash and hype -- the nicknames Pretty Boy and Money, the press-conference posturing, the WWE playacting -- can obscure the fact that Mayweather, 32, is probably the most technically proficient and complete fighter of his generation. Almost literally raised in the gym, he is also one of the hardest workers in the sport. He's witheringly fast, a crisp puncher with either hand, almost untouchable on defense and a master tactician. Undefeated in his 18 bouts in the 2000s, Mayweather (40-0, 25 KOs overall) amassed titles in five weight classes and dismantled a number of first-rate fighters, including Diego Corrales, Jose Luis Castillo, Oscar De La Hoya and Juan Manuel Marquez. The only flaw in Floyd? He didn't face as many of the best fighters as he might have (Shane Mosley and Miguel Cotto, among others) and thus has yet to have that career-defining showdown. That will change when he faces Pacquiao. But that's for another decade.
Hopkins, who turned pro in 1988, was one of the best fighters of the '90s. But he's been even better in the 2000s. A true throwback who would have been at home with the best of any decade, B-Hop went 14-3 this decade (and a case could be made that he won at least one of his two bouts with Jermaine Taylor), capping off a record run as middleweight champion before moving up to take the light heavyweight crown. And at 44, he's still not done. Hopkins (50-5-1, 32 KOs) may not be the most exciting performer, but he could do more in the ring than any fighter of his era: box, counterpunch, bang, break you down, rough you up and always outthink you.
Though he was undefeated and had held the WBO super middleweight title since 1997, the Pride of Wales went largely overlooked outside of, well, Wales, until 2006, when he tore apart overhyped American Jeff Lacy for the IBF belt. Suddenly, folks beyond the U.K. realized the rangy southpaw with the nonstop attack was a hell of a fighter. Calzaghe, 37, may not have been a huge puncher, but he made up for it with speed and an unreal work rate, in addition to a capacity for adapting in the ring. He tallied a 19-0 record this decade (46-0, 32 KOs overall), crowned by a narrow decision over Hopkins and, for his final victory, a first-class butt-kicking of Roy Jones Jr.
During the 1990s, Mosley went undefeated while establishing himself as one of the best lightweights ever. As he moved up in weight over the past 10 years, he lost a few bouts but, if anything, enhanced his status as one of the most compelling fighters of his generation. He was 13-5 with one No Contest this decade (46-5, 39 KOs overall), having defeated such stars as De La Hoya, Fernando Vargas and Antonio Margarito. A superb boxer with crackling speed of hand and foot, Sugar Shane can also punch and brawl when he wants. Now 38, Mosley closed out the decade in style with dominating knockouts of Ricardo Mayorga and Margarito.
Juan Manuel Marquez
Though he was overmatched in his last fight of the decade, against the naturally bigger Mayweather Jr., Dinamita, 36, had established himself as a Hall of Famer long before that. A brilliant technical boxer and a gifted counterpuncher, Marquez was 20-3-1 in the 2000s (50-5-1, 37 KOs overall) against the best competition in four weight classes (from featherweight to welterweight). He had big wins over Marco Antonio Barrera, Joel Casamayor and Juan Diaz, and he fought Pacquiao twice, coming away with a draw and a disputed loss by decision.
Marco Antonio Barrera
Barrera opened the decade with a narrow loss to fellow Mexican hero Erik Morales in the first bout of a spectacular trilogy that played out over three weight classes (from super bantam to junior lightweight). Barrera would go on to take the next two. The Baby-Faced Assassin, 35, a tremendously accurate puncher with a great jab and punishing body attack, went 16-5 this decade (65-7, 43 KOs overall). Even beyond his classics against Morales, Barrera deserves a medal for his encyclopedic schooling of the irritating popinjay Naseem Hamed in 2001.
Remember, this is a list of the best fighters of the decade, not the most exciting. So welcome, Winky! A southpaw with a hunt-and-pop jab, impeccable defensive skills and a constitutional aversion to mixing it up, Wright, 38, turning self defense into an art form and made many of the best welterweights and junior middleweights of the decade look silly. Many of the others simply refused to fight him. Wright went 12-2-1 this decade (51-5-1, 25 KOs overall), with wins over Felix Trinidad, Ike Quartey and Mosley. Granted, he had just one knockout these past 10 years, but what do you expect from a guy with the nickname Winky?
While Wonjongkam may be the smallest man on this list, he has the biggest record. A national hero in Thailand, the 32-year-old longtime flyweight champion went 43-1-1 in the 2000s, with an overall record of 74-3-1 with 39 KOs. A slick-boxing southpaw, Wonjongkam could also produce some surprising power. Since his professional debut in 1994, he has fought exclusively in the Far East.
From the smallest to the biggest. (You could fit two Pacquiaos in his trunks and still have room for half the Wonjongkam family.) Though the bulk of his career took place in the 1990s, Lewis, 34, pretty much dwarfed the heavyweight division during the 2000s. Mature, in full command of a complete arsenal of skills and supremely confident, Lewis went 6-1 with five KOs, extending his career record to 41-2-1 with 32 KOs. He avenged his only loss, a shocking upset by Hasim Rahman, with a definitive knockout in the rematch nearly five months later. In watching him destroy an admittedly faded Mike Tyson in 2004, there was no reason to think Lewis wouldn't have done the same to a prime Iron Mike.
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