LAS VEGAS -- The wait has been three years for a third helping of the great Manny Pacquiao-Juan Manuel Marquez rivalry, but will it be worth it? And will the outcome provide closure to one of boxing's greatest modern rivalries?
They have met twice before in epic battles that ended in controversial decisions, a draw in their 2004 featherweight championship fight and a Pacquiao split-decision victory in the rematch, a 2008 junior lightweight championship bout.
And now they meet again Saturday night (HBO PPV, 9 ET, $54.95) for Pacquiao's welterweight title at the sold-out MGM Garden Arena, the same site as the first fight. Each has something to prove in one of boxing's all-time trilogies.
"The first two fights were as close as any two fights could be," Top Rank promoter Bob Arum said. "This fight will conclusively demonstrate who the better fighter is and settle a point of contention which has been going on for years."
Said Pacquiao: "This will be an exciting fight because our styles make for exciting fights. He likes to fight toe-to-toe, as I do. We both like action and to engage our opponents. I expect Marquez to be faster and stronger than the last time we fought. He is the ultimate competitor. I am prepared to go another brutal 12 rounds just like the previous two fights.
"There will be a lot of action in this fight. We both have a lot of pride when we enter the ring representing our countries, fighting for the honor of our nations."
Pound-for-pound king Pacquiao, the singing congressman from the Philippines and the only eight-division titlist in boxing history, is a significant favorite. He aims to leave no doubt about his superiority against lightweight champion Marquez, the popular Mexican star and three-division champ who is moving up in weight.
"Marquez has the right to make alibis about not winning our two previous fights," Pacquiao said. "It's because of those alibis that I am so motivated for our upcoming fight. I want to end all the questions he has raised about who won our past fights and who the better fighter is. I have something to prove in this fight."
Pacquiao (53-3-2, 38 KOs) has every reason to believe he is the better man, even if many believe Marquez was the rightful winner the first two times. It is Pacquiao who is 1-0-1 against Marquez (53-5-1, 39 KOs), having knocked him down a total of four times -- three times in the first round of the first fight and once in the third round of the rematch.
"I just want to clear out the doubts in the minds of some fans," Pacquiao said.
There are three significant differences between then and now, which Pacquiao believes will make a big difference for him.
One is that he is now a seasoned welterweight (although the fight is contracted at 144 pounds, three fewer than the division limit) used to fighting bigger men.
"I'm bigger. I've been fighting bigger guys for a few years now -- [Antonio] Margarito, [Oscar] De La Hoya, [Shane] Mosley, Miguel Cotto," Pacquiao said. "They're all big."
And Pacquiao beat all of them in resounding fashion.
Another attribute that Pacquiao, 32, points to as an advantage is his evolution as a fighter. Back when he and Marquez previously met, Pacquiao was essentially a one-handed fighter. He's a southpaw and his left hand is deadly, but his right hand was not much of a weapon. He and trainer Freddie Roach have worked on it for years, and it has since become very dangerous and a big part of his arsenal.
"It's a big difference. My right hand is well-developed and I know how to fight," Pacquiao said. "I am a more complete fighter than when we fought previously. I am now a two-fisted fighter. My right is as potent, as powerful and as dangerous as my left. I have as much confidence in my right as I do in my left."
There is also the fact that Marquez, 38, who can brawl with the best of them, is a counterpuncher at heart and gave Pacquiao problems.
"I've been studying since the last two fights how to fight a counterpuncher," Pacquiao said. "Before, we didn't study how to fight a counterpuncher. Now we have perfected how to fight a counterpuncher."
There is another factor, although it is an intangible: Pacquiao's desire to make a statement. Although he takes the high road and has shown Marquez immense respect, there is a palpable sense that Pacquiao wants the knockout.
Those around him say he felt disrespected by Marquez, who has cried for years that he was robbed in both fights, who took to wearing a T-shirt at public appearances that proclaimed in bold letters, MARQUEZ BEAT PACQUIAO TWICE.
"He is tremendously invested in this fight, emotionally invested in this fight," Arum said of Pacquiao. "He wants to win and win convincingly."
Roach has been outspoken about the desire for a knockout victory.
"Manny never predicts and will never say anything bad about this guy, but [Marquez] slapped him in the face when he went to the Philippines wearing a shirt that said 'I beat Manny twice,'" Roach said. "Manny doesn't like this guy, I know that. It's been a little extra motivation for him. And I think after [Floyd] Mayweather couldn't knock this guy out, I think we need to knock this guy out, especially after the last fights [decisions against Mosley in May and Margarito last November] where Manny carried both guys. At this stage, we need a good ending. A knockout is always good."
Not surprisingly, Roach said he strongly believes Pacquiao won both fights.
"I think Manny won both fights, though Manny made them closer than they should have been," Roach said. "I'm worried that Marquez could have Manny's number. He is the only fighter who seems to have figured out Manny's style. That is why I am training Manny for the knockout -- to clear the air on who is better. Manny is going to shut up Marquez once and for all. I'm sick of his whining."
Marquez, a significant underdog at the MGM's sports book, is out to prove that his excellent performances against Pacquiao were no accident and that he can finally get an official win against his greatest rival -- even if it comes in a weight class where, in his only previous fight, he got knocked down and lost a virtual shutout decision to Mayweather in 2009.
"We are going to clear all the doubts from the first two fights, and I feel very good about it," said Marquez, who has added muscle as he has bulked up. He believes the Mayweather fight should be discounted, saying he did not put on the weight properly last time.
"I had problems moving up, but I would rather fight Pacquiao three or four more times than fight Mayweather once," Marquez said. "Mayweather is a defensive fighter -- he doesn't let you fight. But we know Pacquiao comes to fight and he is a spectacular fighter. He is always going to give you a fight, and that's why I know it will be a war between us."
Marquez said he isn't concerned about the fact that he is an older fighter now. He blitzed through Likar Ramos in the first round in a July junior welterweight fight that was a farce, as Ramos basically laid down. In Marquez's most recent real fight, he stopped Michael Katsidis in the ninth round of a lightweight title defense last November -- but he was badly hurt, dropped in the third round and nearly knocked out.
"I don't believe age has anything to do with it," Marquez said. "I prepare myself very well and I'm going to be just as good as I would have been a few years ago. As long as I had the good training camp that I had, I'll be fine."
As sick as Pacquiao is of hearing about it, Marquez doesn't back off his claim that he was the rightful winner of the first two fights.
"Well, if he is upset about what I said about winning the first two fights, I am upset that I didn't get the decision," Marquez said. "I am motivated just as much as he is. We all have opinions and my opinion is that I didn't get the decisions I deserved.
"All the preparation has been done. Now it's just about having the fight of my life to settle everything once and for all."
While Pacquiao isn't willing to make any sort of predictions -- a politician at heart, it seems -- Roach is happy to do it for him.
"Marquez will be surprised when he faces this version of Manny," Roach said. "He no longer fights in one direction or with one hand. Manny has become a complete fighter. He moves laterally in both directions and he throws potent punches with both hands. Manny has so many more weapons than the last time they fought. I think Manny knocks out Marquez in the sixth round."
Dan Rafael is the boxing writer for ESPN.com. Follow him on Twitter @danrafaelespn.