Floyd Mayweather Jr has insisted that he did not violate doping rules prior to his bout with Manny Pacquiao in May.
A report has suggested that the undefeated 38-year-old was given an IV drip, which would be a breach of rules, but the US Anti-Doping Agency has released a statement to dismiss suggestions that they offered him special treatment.
Mayweather, who beat Pacquiao on a unanimous points decision in Las Vegas, claims that there is no case to answer.
"I follow and have always followed the rules of Nevada and USADA, the gold standard of drug testing," the American told reporters.
"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."
Mayweather will meet Andre Berto in what is scheduled to be his 49th and final bout on Saturday.
