Philippine boxer Manny Pacquiao called for punishment and a rematch on Friday after his fierce rival Floyd Mayweather was accused of violating anti-doping rules in the build-up to their mega-fight in May.

The eight-division world champion, who lost a unanimous decision to Mayweather in Las Vegas, urged Nevada sports officials to "impose the appropriate sanction" on the unbeaten American.

Mayweather and the United States Anti-Doping Agency (USADA) have both insisted the boxer's actions were legal after it emerged he was injected with vitamins and minerals before the fight.

But Pacquiao questioned why USADA only informed the Nevada State Athletic Commission (NSAC) about the infusion three weeks after the bout, by which time Mayweather had already received a USADA exemption.

"Are they hiding something? For the sake of fairness and for the good of the sport, NSAC must be consistent," he told reporters at his home in the southern Philippines.