The fallout from the “Fight of the Century” became murkier yesterday with Manny Pacquiao likely to face disciplinary action for failing to disclose a pre-bout shoulder injury.

Filipino Pacquiao lost on a unanimous decision to Floyd Mayweather Jr in a heavily hyped welterweight showdown in Las Vegas on Saturday that is expected to be the top grossing prize fight of all time.

Barely one hour after the contest ended, Pacquiao’s promoter, Bob Arum, said the 36-year-old southpaw had been hampered by an ‘old’ injury to his right shoulder.

On Monday, an MRI scan in Los Angeles confirmed the boxer has a torn rotator cuff that will require surgery.

The major problem here is that apparently neither Pacquiao nor his team informed the Nevada Athletic Commission about the shoulder issue until a couple of hours before the start of the fight when they asked for an anti-inflammatory injection.

At that point, it was too late for the commission to investigate whether or not Pacquiao was suffering a genuine injury and there were no MRIs or medical paperwork to support the claim made by the boxer’s team, the commission said.

While the commission was seemingly kept in the dark, and clearly no boxer wants to give an opponent any hint of possible weakness or injury ahead of a fight, the United States Anti-Doping Agency (USADA) was fully aware of Pacquiao’s injury.

The Filipino suffered the injury during a sparring session at the Wild Card Boxing Club in Los Angeles last month and USADA, after being consulted by Team Pacquiao, permitted treatment through Toradol, a non-steroidal anti-inflammatory.