Manny Pacquiao will undergo surgery on a shoulder injury this week and could be out of action for up to a year following his unanimous points defeat by Floyd Mayweather, according to reports in the United States.

At face value, it may have appeared more than a little crass of the Asian Tour to go ahead with the Manila Masters last week in the wake of the devastation that visited other parts of the Philippines in the form of Typhoon Haiyan.

Manny Pacquiao retained the WBO Welterweight World Championship with an unconvincing unanimous points victory over Sugar Shane Mosley in Las Vegas.