Manny Pacquiao of Philipines to undergo shoulder surgery.

Mayweather punching Pacquiao on shoulder, does it mean he knows he has an injury?

Manny Pacquiao’s camp accused the Nevada Athletic Commission on Monday of denying them treatment for an injury to his right shoulder which will now require surgery to repair.

Pacquiao, who lost a unanimous decision to Floyd Mayweather in their welterweight unification fight on Saturday, is expected to undergo surgery later this week for a torn rotator cuff, ESPN reported on Monday.

Dr. Neal ElAttrache described the tear as “significant” and said Pacquiao could be out between nine and 12 months.

“We have an MRI scan that confirms he has a rotator cuff tear. He has a significant tear,” ElAttrache of the Kerlan Jobe Orthopedic Clinic told ESPN.

Floyd Mayweather Jr. throws a left at Manny Pacquiao during their welterweight unification championship bout on May 2, 2015 at MGM Grand Garden Arena in Las Vegas, Nevada. Al Bello/Getty Images/AFP

ElAttrache is one of the most respected surgeons in North America, having operated on New England Patriots quarterback Tom Brady, Los Angeles Dodgers pitcher Zack Greinke and Los Angeles Lakers star Kobe Bryant.

No specific date has been set for the surgery.

Pacquiao and Mayweather met at the MGM Grand in Las Vegas in one of the most anticipated showdowns in boxing history which promises to be the richest fight ever with revenues of about $400 million.

The super fight also cemented Mayweather as the top pound-for-pound fighter of the era but that was before severity of Pacquiao’s injury was revealed.

The southpaw clearly had difficulty with his right hand during the 12-round title fight as he landed just 18 jabs, compared to 67 for Mayweather. The injury also limited Pacquiao’s power punches as he connected on just 27 percent compared to the defensively-minded Mayweather who connected on 48 percent.

Pacquiao’s camp said the Commission refused them treatment on fight night despite them having prior approval to use an anti-inflammatory injection by the United States Anti-Doping Agency (USADA), which conducted random drug testing on the boxers in the build-up to the fight.

Pacquiao’s camp had planned give him Toradol, a non-steroid anti-inflammatory, just before the fight, but the Commission stepped in and halted the treatment. The Nevada Commission, which oversees boxing in the state, said they were not told about Pacquiao’s injury until the night of the fight.

Pacquiao’s team said USADA approved the injection five days before the fight and they disclosed their desire to use it on fight night in their medical forms.

– Treatments ‘approved’ –

“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 camp said in Monday’s statement.

Pacquiao said he hurt the shoulder in training camp some three weeks before the bout, and they considered postponing the contest dubbed the “Fight of the Century” by promoters.

His camp said when the injury first happened, Pacquiao visited the ElAttrache’s Kerlan Jobe Orthopedic Clinic in Los Angeles and he was told to treat it with rest before resuming his heavy training regime for the fight.

After some rest, Pacquiao continued to work with trainer Freddie Roach who felt, along with promoter Bob Arum, that the injury had improved enough to allow the fight to go ahead.

“Manny continued to train and his shoulder improved, though not 100 percent,” the statement said. “With the advice of his doctors, Manny still decided to proceed with the fight. His shoulder wasn’t perfect but it had improved in camp.