Pacquiao could also face a possible fine or suspension after answering ’no’ on a Nevada Athletic Commission (NAC) questionnaire ahead of the welterweight unification showdown in Las Vegas last Saturday.
He did not submit any injuries before the fight, but cited a shoulder problem after it.
”We were planning to postpone because for two weeks I didn’t train well. We couldn’t do what we wanted to because of my shoulder,” Pacquiao said after the bout.
He could now be set to spend time out of the ring while he recovers.
Orthopedic surgeon Dr Neal ElAttrache said Pacquiao, 36, will have surgery to fix a “significant tear” in his rotator cuff this week which looks set to enforce a nine to 12-month absence from the ring.
The surgeon is understood to have examined Pacquiao in Los Angeles on Monday.
NAC executive director Bob Bennett said: “It’s not just the fact he didn’t fill out the question completely, it was that he wasn’t honest and they didn’t tell us when he had the shoulder injury.
“They’re not obligated to, but two hours before the fight they wanted a shot that’s a painkiller, in essence. That put us in a very precarious position.”
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.
Pacquiao’s promoter said in a statement on Monday that doctors had “concluded that with short rest, treatments and close monitoring, Manny could train and, on May 2, step into the ring against Floyd Mayweather”.
Pacquiao continued to work out and his shoulder improved, “though not 100%”, but he decided to proceed with the fight after anticipating that he could receive his pre-bout treatment.
“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,” Pacquiao’s promoter said.
“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.”
USADA had been informed about the injury but its role was limited only to testing the fighters for banned substances.
The commission was in overall control, yet when Team Pacquiao filled in its pre-fight medical questionnaire on Friday, a query about any shoulder injury was marked clearly “No” before the form was signed by Pacquiao and his advisor. “It’s something we’re looking at, and an issue we’ll be discussing with the attorney general,” commission chairman Francisco Aguilar said. “Boxers are tough, and it’s our job often to protect them from themselves.”
The fact that Pacquiao did not disclose his injury until the night of the fight could also lead to possible lawsuits from boxing fans who feel cheated after paying record sums for either tickets in the MGM Grand Garden Arena or pay-for-view (PPV).