In three attempts, Juan Manuel Marquez has been unable to beat Manny Pacquiao. This weekend, the boxer will get one more chance to pick up his first win in this rivalry.

Pacquiao-Marquez IV is set for Saturday Dec. 8 at the MGM Grand in Las Vegas. Coverage begins on HBO at 9 p.m. ET. Unlike each of the three previous bouts, this will not be a title fight.

Although Pacquiao has gone 2-0-1 in the fighters’ three previous meetings, Marquez had a chance to win each bout. If it weren’t for the three knockdowns he suffered in the first round of their 2004 fight, Marquez might have defeated Pac-Man. Their rematch in 2008 resulted in a split decision, in which many, including Marquez, thought he should have been named the winner.

Pacquiao-Marquez III was also controversial, though Pacquiao won by majority decision.

Despite his previous failures, Marquez is confident entering Saturday. In 36 rounds, he has never been knocked out by his opponent, and he’s only been knocked down once in the last 35 rounds.

Even though he hasn’t been able to knock down Pacquiao, Marquez isn’t ruling out the possibility of delivering a knockout.

"Do I need to knockout Pacquiao to get the win?” Marquez said in an interview with ESPN. “Well, I will certainly try. I also know that while knocking out a fighter like Pacquiao won't be easy, it's not impossible either.”

Pacquiao hasn’t been knocked out of a fight since 1999.

The last fight Pacquiao participated in might have been the most controversial of his 16-year career. He was defeated by Timothy Bradley in a split decision, although many felt he won the fight unanimously. Five WBO Championship Committee judges later admitted that Pacquiao should have been named the winner, though the actual decision was never overturned.

The previous matches between the two boxers have come in all different weight classes. This time around, Pacquiao and Marquez will face off in a welterweight bout. Doing so should benefit Pacquiao, who’s had success moving up in weight classes. The same can’t be said for Marquez, who has struggled in the weight class, losing decisively to both Pacquiao and Floyd Mayweather.

Both fighters have had long, storied careers with 54 wins apiece. If the first three bouts between these two are any indication, this should be a very competitive fight.

Betting Odds: Pacquiao-350, Marquez+275

Prediction: Marquez has come close to defeating Pacquiao in the past, and has proven he can go the distance with Pac-Man. Pacquiao, though, matches up well with his opponent.

He’s one of the best combination punchers around, something that Marquez has been known to have trouble with. Fighting as a welterweight also gives the favorite an advantage. It should be competitive, but Pacquiao will likely remain undefeated in this rivalry.

Pacquiao over Marquez, by a majority decision