LAS VEGAS - Floyd Mayweather Jr. insists he did nothing wrong in taking an IV solution to rehydrate after the weigh-in for his fight against Manny Pacquiao.
Doping officials on Thursday also backed Mayweather, saying he disclosed the infusion to them before taking it and that it contained no prohibited substances.
A report Wednesday by SB Nation said representatives of the U.S. Anti-Doping Agency saw that Mayweather had taken the IV when they went to collect urine samples from him after the weigh-in. The report said the Mayweather did not receive a formal exemption from the USADA for the IV until three weeks after the fight.
But the USADA said it was aware of the IV prior to it being taken and that the Nevada Athletic Commission and Pacquiao's representatives were notified. In a statement, the agency referred to what it called "numerous unfounded and false accusations" in the article, saying they were either a "genuine misunderstanding of the facts or an intentional desire to mislead."
"It is simply absurd to suggest that we would ever compromise our integrity for any sport or athlete," the statement said.
The substances in the IV -- a saline solution and vitamins -- are not banned by the USADA. But the World Anti-Doping Agency does not allow the high volume that Mayweather took because it can mask other substances.
"Although Mr. Mayweather's application was not approved until after his fight with Mr. Pacquiao and all tests results were reported, Mr. Mayweather did disclose the infusion to USADA in advance of the IV being administered to him," USADA's statement read.
It added that once the therapeutic use exemption was granted, the Nevada commission and Pacquiao were immediately notified even though the practice is not prohibited.
Mayweather, who is fighting Andre Berto on Saturday, said he has always been a strong supporter of athletes being clean. His insistence on having the USADA do random testing was one reason his fight with Pacquiao took place five years after it was originally proposed.
''I did not commit any violations of the Nevada or USADA drug testing guidelines," Mayweather said in a statement. "I follow and have always followed the rules of Nevada and USADA, the gold standard of drug testing."