Manny Pacquiao Knockout Video: Watch Pac-Man Get KO'd by Juan Manuel Marquez

Manny Pacquiao never saw Juan Manuel Marquez's thunderous right hand coming. With that destructive counter-punch, Marquez (55-6-1) knocked Pacquiao (54-5-2) out cold in the sixth round of their bout Saturday night, leaving mouths agape as the boxing landscape was fundamentally altered.

In a fight that was an all-out slugfest from start to finish, Pacquiao and Marquez made sure the fourth installment of their epic series will go down as one of the finest. 

From the very beginning of the fight, it was obvious that this bout wasn't going to the judges' scorecards. Aggressive from the outset, Pacquiao took control of the opening two rounds, peppering Marquez with strong left hands and uppercuts to take an early lead.

However, it was Pacquiao's aggressiveness that was ultimately his undoing. In perhaps a precursor of the sixth-round knockout, Marquez connected on a sensational punch in the third that stunned Pacquiao and sent him to the mat. 

After regaining the lead in the fourth round, Pac-Man settled in and looked prepared to dominate. He scored a knockdown of his own in the fifth round and seemed to be sensing Marquez's legs quivering as the final moments of that round looked like Rock 'Em Sock 'Em Robots.

Round 5 left Marquez's nose broken and dripping blood, something that came heavily into play in the deciding moments of the fight.

Again with the momentum at his side and sensing a possible knockdown, Pacquiao aggressively stalked Marquez down to the final seconds of the sixth round round. With mere seconds remaining on the clock, one misstep sent the Filipino star dropping to the canvas. It was the first knockout loss Pacquiao had suffered since 1999 and will almost certainly set up a fifth fight if both men can agree to terms.

Check out the knockout video provided above to see a scintillating moment that will go down in boxing history.

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