WBA/WBC welterweight champion Floyd Mayweather has carried his unbeaten streak to 47 straight fights with a unanimous decision victory over Argentine Marcos Maidana in their 12-round rematch.

Mayweather, who hasn't lost a fight since the 1996 Olympics, improved to 47-0 as two judges scored it 116-111 and the third had it 115-112 for the champion, who was a heavy favourite coming into Saturday's bout after winning the first fight by a majority decision in May.

"I prepared myself very well and thought I won the fight but if the referee prefers to give the fight to fighters who run, I can't do anything about that. I was the aggressor throughout. I kept my game plan but Floyd was holding and pushing and the referee only punished me. I did not bite him in the eighth round. Maybe they think I'm a dog. I never bit him. He had his glove right on my mouth but I did not bite him," Maidana said.