LAS VEGAS, NV - DECEMBER 08: (R-L) Manny Pacquiao knocks down Juan Manuel Marquez in the fifth round during their welterweight bout at the MGM Grand Garden Arena on December 8, 2012 in Las Vegas, Nevada. (Photo by Al Bello/Getty Images)
Manny Pacquiao - Juan Manuel Marquez IV
Manny Pacquiao was dropped by a vicious right hand by longtime rival Juan Manuel Marquez in the sixth round as the two fought for the
fourth time at the MGM Grand Garden Arena in Las Vegas, Nev. on Saturday, Dec. 8, 2012.