Floyd Mayweather claims he is innocent of any wrongdoing for the "Fight of the Century" against Manny Pacquiao.
A report emerged on Thursday which claimed that Mayweather was given a banned injection before the record-shattering superfigh and had received favourable treatment from the US Anti-Doping Agency (Usada).
The undefeated pugilist allegedly took an intravenous solution of saline and vitamins on the night before the bout, which was banned under World Anti-Doping Agency guidelines.
However, Mayweather has denied he broke any rules by having the solution injected on the eve of the fight.
Mayweather said he was "very proud to be a clean athlete".
The added: "I follow and have always followed the rules of Nevada and Usada, the gold standard of drug testing.
"Let's not forget that I was the one six years ago who insisted on elevating the level of drug testing for all my fights."
It added that the infusion had come to light after Usada agents visited the boxer at his Las Vegas home on 1 May to conduct an unannounced test.
The Usada have also released
a statement in which they claim Mayweather had done no wrong.
"We believe it is important to immediately correct the false suggestion that Floyd Mayweather violated the rules by receiving an IV infusion of saline and vitamins,"
"It is simply absurd to suggest that we would ever compromise our integrity for any sport or athlete.''
