Three-division world champion MARCO ANTONIO BARRERA, has declared war on his opponent and nemesis, pound for pound superstar Manny Pacquiao. Barrera, who began his fifth week of secluded high altitude training in Mexico, is preparing to battle and dethrone the reigning "Fighter of the Year" in a 12-round super featherweight boxing rumble 2. Marco Antonio Barrera will fight Manny Pacquiao on October 6th at Mandalay Bay in Las Vegas, Nevada..