Manny Pacquiao
Manny Pacquiao will undergo a shoulder surgery that could keep him away from the ring for nine to 12 months, according to reports. Reuters/Steve Marcus

Manny Pacquiao will undergo surgery on his right shoulder later this week to repair a torn rotator cuff, media reports said Monday. Pacquiao, who was beaten by Floyd Mayweather on Saturday night at the MGM Grand in Las Vegas, hurt himself while training for the fight, which was billed as the most expensive pay-per-view boxing event.

However, Pacquiao could face disciplinary action from a Nevada boxing authority for failing to report the shoulder injury ahead of his fight with Mayweather, according to Fox Sports. Nevada Athletic Commission Chairman Francisco Aguilar reportedly said that the state attorney general's office will investigate why Pacquiao did not disclose his injury on a commission questionnaire before the fight.

"We will gather all the facts and follow the circumstances," Aguilar reportedly said. "At some point we will have some discussion. As a licensee of the commission you want to make sure fighters are giving you up-to-date information."

Pacquiao’s trainer Freddie Roach said that the boxer got hurt when his shoulder hit a sparring partner's about four weeks before the fight, which was one of the most-anticipated in the sport’s history. And while Pacquiao took anti-inflammatory shots approved by the United States Anti-Doping Agency (USADA) during training, the commission did not allow him to take any shots before Saturday's fight because he did not make his injuries known on a medical form, according to reports.

However, a joint statement from Pacquiao and his promoter, Top Rank Boxing, denied the claims.

"On his pre-fight medical form filled out earlier in the week, Manny’s advisors listed the medications that Manny used in training and the medications that might be used on fight night. A few hours before he was expected to step in the ring, when Manny’s doctors began the process, the Nevada Commission stopped the treatment because it said it was unaware of Manny’s shoulder injury," the statement read. "This was disappointing to Team Pacquiao since they had disclosed the injury and treatment to USADA, USADA approved the treatments, and Manny had listed the medication on his pre-fight medical form."

Pacquiao's manager Michael Koncz said, according to the Los Angeles Times: "Manny and [his wife] Jinkee decided that in the best interests of his long-term health, he will have the surgery here this week," adding: "Following surgery, we will have a fuller assessment of the situation, and doctors will follow with an announcement on Manny's prognosis," Koncz said.

Pacquiao’s surgery is expected to keep him out of the ring for nine to 12 months.

"Two weeks before the fight, my shoulder was getting better and better, but it still wasn't 100 percent," Pacquiao said, after losing to Mayweather, adding that the injury hampered him during the fight where Pacquiao managed to go the full 12 rounds against Mayweather before losing the bout by unanimous decision.