World champion Manny Pacquiao will take on Juan Manuel Marquez for the fourth time tonight at the MGM Grand in Las Vegas, Nevada. The fight between Pacquiao (54-4-2, 38 KO) and Juan Manuel Marquez (54-6-1, 39 KO) has been sold out and millions of fans around the world are anticipating fight for of the two elite boxers. 

The respective boxing card is slated to bring in 1 million pay-per-view purchases at the bare minimum, which is just about the same amount as their third fight (1.3 million in purchases).

In the eight years that have passed since the two future hall of famers first squared off, Pacquiao and Marquez have fought three previous fights, in which their time in the ring opposing one another has totaled 108 minutes.

Pacquiao will more than likely head into the matchup as nimble as ever.  However, he is coming off a loss to Timothy Bradley, which was his first since his bout against Erik Morales in 2005. 

While the defeat to Bradley was a win to a majority of subjective viewers, he was clearly outdueled down the wire in the championship rounds, something that would've been unheard of in 2009.

Nonetheless, Pacquiao is a mere nine days from turning 34-years-old and isn't the same physical boxer he was a couple years back against the likes of Ricky Hatton and Miguel Cotto.

With the sheer athleticism of Pacquiao and the in-ring skills of Marquez, the latest battle should shape up to be another rapid punch-trading war.

In terms of the fight purse, Pacquiao is expected to rake in roughly $30 million while Marquez will make an estimated 10 million. 

If the Pacquiao-Marquez PPV well exceeds the one million mark in terms of the buy rate, then it would actually be possible for a fifth fight to take place in 2013, according to IMTV.

CLICK HERE to watch Manny Pacquiao take on Juan Manuel Marquez via live stream.  Coverage of the boxing match is set to begin at 9 p.m. ET.