Floyd Mayweather Jr (File)

New York - Floyd Mayweather Jr. and welterweight champion Shane Mosley will undergo Olympic-style drug testing for their May 1 fight in Las Vegas, which they hope will set a new standard for boxing.

Representatives of the two fighters joined Travis Tygart of the US Anti-Doping Agency on a conference call on Thursday to discuss the program, which is more extensive than the testing that currently falls under the jurisdiction of state athletic commissions.

"This is one of the biggest events I've seen in the sport of boxing, and if this introduces Olympic-style testing to boxing, we not only have delivered a great fight but also leveled the field for athletes," Richard Schaefer of Golden Boy Promotions said.

Mayweather and Mosley will be subjected to an unlimited number of unannounced blood and urine tests before and after the fight, and the results will be stored so USADA can test them in the future. The samples are screened for all drugs currently banned by the World Anti-Doping Agency, including human growth hormone and designer steroids such as THG.

Most state athletic commissions test only urine samples, which Tygart said cannot detect several performance-enhancing substances, including HGH.

"For the first time, you have professional athletes in the sport of boxing approaching us to implement an anti-doping program," Tygart said. "These athletes are courageous in their position and their desire to be held to the most stringent anti-doping standard."

Mayweather's insistence on Olympic-style testing is the primary reason negotiations fell through in January for a fight against pound-for-pound king Manny Pacquiao. Mayweather wanted blood tests up to 14 days before the fight, while Pacquiao claims he feels weak after drawing blood and would not agree to testing within 24 days.

Pacquiao promoter Bob Arum accused Mayweather of trying to get into his fighter's head by alleging that he used steroids. The negotiations quickly deteriorated, and Pacquiao signed to fight Joshua Clottey while Mayweather turned his attention to Mosley.

"With Floyd being the face of boxing, this is something that he has wanted to put forth," said Mayweather's adviser, Leonard Ellerbe. "Every fight from this point on that anybody steps into the ring with him will be subjected to this."

That begins with Mosley, who has acknowledged using steroids before a victory over Oscar De La Hoya in 2003. The four-time world champion claims he did so inadvertently through a strength and conditioning coach with connections to BALCO, the center of the scandal that enmeshed Barry Bonds and several other high-profile athletes.

Mosley filed a defamation lawsuit against Victor Conte after the BALCO founder said the boxer knowingly took performance-enhancing drugs.

"I want to be clear that Shane would not be doing this if there were any doubt in his mind that he's a clean athlete," said Mosley's lawyer, Judd Burstein. "Shane has never denied, right from the start, he made a mistake with respect to trusting Victor Conte.

"Shane is doing this, and Floyd is to be congratulated for being on the forefront here, but Shane didn't hesitate because he knows he's a clean athlete."

Tygart said USADA, which has been involved in the BALCO investigation, discussed the Mosley case before agreeing to implement its drug-testing program.

"You have to remember that professional boxing entities that had jurisdiction over him at the time did not bring any discipline over those allegations or any others," Tygart said. "If those allegations were ever proven to be true and he was sanctioned, he would have served his time by this point and would be eligible to compete."

While the two fighters have agreed to the more rigorous testing for their bout at the MGM Grand, it will ultimately come down to whether sanctioning bodies and state athletic commissions choose to recognize punishments that USADA might impose.

That could include a two-year ban for a failed test.

"At the end of the day, USADA has no jurisdiction," Keith Kizer, executive director of the Nevada Athletic Commission, told The Associated Press. "Like any medical test, if a fighter wants to do anything more than what we require, more power to them."

Kizer said fighters can petition the commission to change its drug testing protocol, and Arum was open to doing that in December, before negotiations for Pacquiao-Mayweather unraveled.

Schaefer took that option to Mayweather's team, but Kizer said they never responded.

"At the end of the day, this is about Pacquiao-Mayweather, and we're not going to change our policies to help one fighter get a mind-game edge or another edge over another fighter," Kizer said. "That being said, we have over the years revised and expanded our policy. We added steroid testing about nine years ago, out of competition testing a few years back.

"More drug testing is better, everyone would agree to that, but there is a limit."