LAS VEGAS – Juan Manuel Marquez knocked Manny Pacquiao out cold with a vicious right hand at the end of the sixth round Saturday night, putting a ferocious end to the fourth fight between the two boxers.

Pacquiao had been down in the third round but knocked Marquez down in the fifth, and the two were exchanging heavy blows in the sixth round before Marquez threw a right hand that flattened Pacquiao face down on the canvas at 2:59 of the sixth round.

The referee waved the fight to an end as Marquez celebrated and the sold-out crowd at the MGM erupted. Pacquiao was down for about two minutes before his handlers managed to get him up.