Amir Khan's May 19th rematch with Lamont Peterson is in doubt after the American tested positive for a banned substance.
The fight is scheduled to take place in Las Vegas, five months after Peterson stunned the WBA and IBF light-welterweight champion in their controversial first clash.
But on Monday night, Peterson's attorney, Jeff Fried, issued the following statement: "We have tremendous respect for VADA [Voluntary Anti-Doping Association] and its mission. Lamont, [his trainer] Barry [Hunter] and the entire team emphatically support random drug-testing in the most comprehensive manner possible.
"We are working expeditiously with a team of pathologists and other medical specialists. Lamont has never had a positive test either before or after this isolated occurrence and we plan to submit medical findings by close of Tuesday reflecting the actual facts in support of Lamont's good faith intentions and the requirements of the commission."
Reports suggested Peterson has tested positive for synthetic testosterone, and although there is no evidence of him being guilty of any wrongdoing, the substance can be used to increase muscle strength, as well as shortening recovery time.
Peterson had earlier this year suggested both boxers undergo Olympic-style drugs testing in the build-up to the fight.
"It's not that we think Khan is cheating or anything. It's just that there are people who are out there cheating and they have new methods of cheating," he said back in March.
"And we do urine tests all the time so why not take blood tests and make sure everyone is safe in the ring."