Manny Pacquiao (53-3-2) and Juan Manuel Marquez, (53-5-1) are set to battle in their highly anticipated rubber match at the MGM Grand Arena in Las Vegas, Nevada, on Saturday night.

In 2004, the two boxing stars fought to a draw as featherweights. In 2008, Pacquiao and Marquez fought as super featherweights, and Pacquiao won in a narrow split decision. This time the WBO welterweight title will be on the line.

It will be more than three and a half years since the epic 2008 bout, and styles and attitudes have changed in that time, but the resentment for the past decisions has not.

This fight represents unfinished business for both boxers based on how the last two fights ended, as each has a great deal to prove against their respected opponent.

Pacquiao, 32, seeks a convincing victory to help critics forget that Marquez gave him two competitive fights. It would also strengthen the Filipino icon's credibility that he is better than fellow welterweight boxer Floyd Mayweather Jr., who thoroughly defeated Marquez in 2009. A megabout with Mayweather is looming, but should that fight not take place, Pacquiao will have already established himself as perhaps the best pound-for-pound boxer of his generation should he score a clear victory on Saturday.

Marquez, 38, fully believes that he won the 2008 fight, and went so far as to wear a t-shirt that read We Were Robbed. Marquez's reputation will be on the line since he has never defeated a superstar boxer and considering the Mexican star may only have a few more fights left. In a country that still worships Julio Cesar Chavez, Marquez could elevate to perhaps a similar status in his homeland by defeating Pacquiao.

With a possible bout with Mayweather looming, Pacquiao's performance will be highly scrutinized. The southpaw is very aware of how well Mayweather was able to defeat Marquez, and should Pacquiao and Mayweather fight, the upcoming fight with Marquez will be a key reference.

Pacquiao and Marquez will battle at a 144-pound catch weight.

ODDS: Pacquiao is favored 9-1, according to bodog.com

Here is a breakdown on both fighters:

TALE OF THE TAPE:

                Pacquiao     Marquez

AGE:        32                 38

HEIGHT:   5'6 ½            5'7

WRIST:     8                  6.5

REACH:    67                67

STANCE:  Southpaw     Orthodox

RECORD: 53-3-2          53-5-1

Who has the edge?

TRAINER: Ignacio Nacho Beristain is a Hall of Fame trainer and has taught some of the most prominent Mexican fighters in the world, and has generally flown under the radar. Meanwhile, Freddie Roach is also a no-nonsense trainer, but his effects on Pacquiao over the years has been tremendous as the boxer has steadily improved.

EDGE: Slightly for Pacquiao

EXPERIENCE: Each boxer has about the same number of fights. Marquez is older and has grown up in a boxing family with brother Rafael, and lived in a neighborhood where he was pushed to fight. Pacquiao has more fights as a welterweight, and has looked far more comfortable than Marquez in the weight class.

EDGE: None

SIZE: There has been a lot of coverage about Marquez bulking up, which some suggest is a disadvantage. Marquez is a little taller than Pacquiao. Considering they're at a catch weight of 144, size probably won't be much of a factor.

EDGE: Slightly for Marquez

SPEED: Marquez and Pacquiao have focused on speed in their training sessions. Marquez's camp has acknowledged that Pacquiao is the faster boxer, but Marquez has made strides in this area and likely won't look as sluggish as some might expect.

EDGE: Pacquiao

STRENGTH: Both boxers have knockout power, while Marquez appears to embrace a slug fest. Based on coverage from HBO's program 24/7, it seems Pacquiao is very determined to knock out Marquez, and his aggressive style will likely show off his power. His one-shot power was evident in his convincing win over Ricky Hatton.

EDGE: Pacquiao

STAMINA: Pacquiao's intense training won't mean he'll tire in this fight, which has been the cause of some concern from those who have kept a close eye on him. Marquez has a track record of going the distance and getting up once he's been knocked down. Pacquiao is younger, and looks like the Energizer Bunny in training sessions.

EDGE: Slightly for Pacquiao

CHIN: Both fighters have been hit hard in their career, and handle their punches. While Pacquiao had the ability to walk through Miguel Cotto's punches, Marquez finds a way to recuperate after being knocked down, as proven by his win over Michael Katsidis.

EDGE: Slightly for Marquez

DEFENSE: Neither is a defensive specialist, but since Pacquiao will be the more aggressive of the two boxers, he will leave himself open to be hit. Counter-punching is Marquez's style, and will likely be his main strategy against Pacquiao. It would make sense for Pacquiao to dance and make Marquez chase him, but that has never been Pacquiao's style. The Filipino star often lowers his fists, and prefers to go toe-to-toe and accept some punishment due to his confidence in his power. Marquez appears to thrive off of opponents' delusion that they are a punch away from winning by knockout, and has never lost a fight via knockout.

EDGE: Marquez

MOTIVATION: Pacquiao and Marquez have a lot riding on this fight. Pacquiao seems more desperate to floor Marquez, and it would be devastating for the Filipino icon to lose to a boxer that lost to Mayweather. Marquez is hungry for a win, because he feels he had been robbed and his pride has been hurt. Pacquiao simply wants it more as a huge payday looms.

EDGE: Pacquiao

PREDICTION: This will not be quite the exciting fight people expect. Both boxers will feel each other out in the opening round, but in Round Two, Pacquiao will come out firing, and Marquez will have to sustain the barrage. Marquez is bound to go down in the middle rounds, because Pacquiao's power will simply overwhelm him. However, Marquez will win rounds because he will sense the fight will go the distance and pace himself well. Pacquiao wants to win this fight more than Marquez, and he will probably score a technical knockout by Round Nine.