LAS VEGAS -- Manny Pacquiao, the pound-for-pound king, stands on the precipice of history. In his way stands junior welterweight world champion Ricky Hatton.
But if Pacquiao, fighting for the first time as a junior welterweight, can defeat Hatton, the long-reigning champion who has never lost at 140 pounds, in their much-anticipated showdown at the MGM Grand on Saturday night (HBO PPV, 9 ET), the Filipino icon will enter rare air.
• A Pacquiao victory would give him a world title in a record-tying sixth weight division -- flyweight, junior featherweight, featherweight, junior lightweight, lightweight and junior welterweight.
Yes, there was a time when there were only eight weight classes with one champion per division, and now there are 17 divisions with four sanctioning organizations handing out the most recognizable titles. But if it were easy to win titles in six divisions, everyone would be doing it. So far, only one man has: Oscar De La Hoya, who won belts from junior lightweight to middleweight before Pacquiao sent him into retirement by handing him a beating in a nontitle welterweight bout in December.
• If Pacquiao (48-3-2, 36 KOs), the betting favorite, dethrones England's Hatton (45-1, 32 KOs), he will accomplish something no fighter in boxing history has ever done, which is to claim the lineal championship in a fourth division. Lineal, as in the man who beat the man, who beat the man, who beat the man, etc. In other words, he'll be considered the "real" champion in a fourth division, not just a mere titleholder, the way he was when he claimed his junior featherweight belt and lightweight title.
"Pacquiao goes down as one of the greats if he can accomplish a junior welterweight championship to go along with his other hardware," said boxing historian and occasional ESPN.com contributor Bert Sugar. "Reason being -- it's not only difficult to leapfrog this many weight classes, but because you have equaled and passed greats like a Henry Armstrong, greats like Alexis Arguello. The way he has done it, we still don't know his true fighting weight. Even with all the belts, he's still the lineal champion in so many weight classes. I make him out to be the greatest Asian fighter of all time and conceivably one of the greatest fighters of all time if he can carry this off.
"Now, we have a lot more titles, but it still does not dim or in any way minimize what Manny Pacquiao has done."
Already a five-division titleholder, Pacquiao is in impressive company. The only others to get one for the thumb? Sugar Ray Leonard, Thomas Hearns and Floyd Mayweather Jr. The four-division titleholders in boxing history are Roberto Duran, Pernell Whitaker, Roy Jones Jr. and the not-so-well-known Leo Gamez.
Pacquiao is reserved about the historical implications of a win Saturday, but he is certainly aware of what is at stake.
"It is very important for me to win [titles] in six different divisions for the people of my country," said Pacquiao, who has always dedicated his accomplishments to the Philippines. "Being a six-division champion, if that happens, people will want to put my name in boxing history, and that will be my legacy."
Freddie Roach, Pacquiao's trainer, admitted that he is surprised that Pacquiao has been able to keep moving up the scale with such success.
"I never thought this would ever happen. When I started with Manny because he was just 122-pound champ," said Roach, who took over Pacquiao's training after he had already been flyweight champion. "He's just been getting bigger and stronger. He's a lot happier when he's not making weight. He's healthier, he gets to eat what he wants, and I feel when I have a happy fighter that's not struggling to make weight, it's a good thing. And his powers come up with him. Manny Pacquiao, he's a machine. He is the hardest worker I've ever seen in my life, and that's why he's the best fighter in the world today."
De La Hoya was considered the lineal champion in three of the weight divisions he won titles in, junior welterweight, welterweight and junior middleweight.
As the only six-division titleholder, he can appreciate what Pacquiao is gunning for.
"He's in a position now where he can make history," De La Hoya said. "It's not easy to jump six weight classes. It's not easy at all. It's probably the most difficult task that any fighter can have. I've always said it was more difficult than just being world champion for 10 years at one weight class."
Even Hatton, who has dominated at junior welterweight for years, although he did claim a belt at welterweight before returning to his natural division, is somewhat in awe of Pacquiao's climb up the scale.
He's with De La Hoya in believing that it's more of an achievement to win titles in multiple divisions than it is to stay in one weight class and systematically clean it out.
"It's a phenomenal achievement what Manny's done. He [turned pro] at 106 pounds. So that's incredible, a man fighting at the weight he's fighting at now," Hatton said. "But I think it's a lot easier to move up through the weights the lighter weight you are because, obviously, the weights are a lot closer together. From where Manny started off when he won his first world title [at 112 pounds] to when he won his last world title [at 135 pounds], you would have to say it's more impressive. Even though the weights are very, very close together, it's absolutely such a massive achievement."
Top Rank's Bob Arum, Pacquiao's promoter, knows a thing or two about fighters moving up in weight. He promoted De La Hoya for virtually all of his career, and he also promoted many of Leonard's biggest fights. He said Pacquiao's background could be a reason why he's been able to start off in such small divisions and steadily move up with success.
"He came from a background where it very hard to gauge his true weight because when he fought early on at flyweight, was it because of the lack of nutrition or was he a naturally smaller guy?" Arum said, noting that Pacquiao grew up in poverty without much food. "Then as he became more affluent and could feed and take care of his body, the fact that he has put on weight and seems to be better with the added weight is not surprising. The conventional wisdom is when a fighter moves up in weight he loses his speed and his power. With Manny just the opposite seems to have happened. His speed is now better, and his power is certainly better.
"Manny is a very unique fighter, and he has a great set of skills that translates itself to going up and down the divisions. It's as simple as that. He outspeeds everybody, and he outpunches everybody. And he never gets tired."
If Pacquiao does make history by beating Hatton, more could be on the way. A title fight at welterweight is certainly not out of the question.
"I don't put it past him to look really good [Saturday] and maybe beat some of the top welterweights," Arum said. "There are welterweights out there that he can compete with, like [Miguel] Cotto or [Floyd] Mayweather [Jr.], that would make very interesting fights in the years ahead. So I am not concerned with his smaller frame. He matches up really well with some of the top welterweights. I really believe that Manny's body of work at this particular time establishes him as one of the great fighters in the history of boxing. I really believe that there is a lot more to come which will cement that legacy."
Pacquiao is game.
"Fighting at 140 pounds is my regular weight, and I am very comfortable at that weight," he said. "But I can fight at other positions. It's about discipline. I have disciplined myself, so that is why I can fight at heavier weights. If the fight is at 147, I can fight at 147. Right now, the fight is at 140, so I have to fight at 140 pounds."
Sugar also wouldn't put it past Pacquiao to beat Hatton and move on to even greater glory.
"What Manny has done sort of defies all reason," Sugar said. "We don't yet know where he will hit that wall. What is the weight at which he can't? We have come to the point where we are watching a phenomenon. I don't know if we will appreciate it now or it will take us years to appreciate it."
Here's what's scary: Pacquiao may not even be at his best yet.
"I believe that I am improving," Pacquiao said. "And everybody knows and can see that by my last few performances."
Dan Rafael is the boxing writer for ESPN.com.