Wayne Odesnik was forced to confront his controversial past on Tuesday as the American hit back at the latest claims about his alleged involvement in a doping row.
Odesnik, the world number 107, was banned for two years in 2010 after trying to import human growth hormone (HGH), an anabolic agent used by drug cheats, into Australia.
The 27-year-old later had half of his ban suspended by the sport's governing body, the International Tennis Federation, when he agreed to give "substantial assistance in relation to the enforcement of professional rules of conduct".
But Odesnik came under fresh scrutiny recently when his name was reported to have appeared in the hand-written records of a Miami clinic at the centre of a developing doping scandal engulfing American sport.
The clinic's founder, Tony Bosch, is being investigated for allegedly supplying banned drugs to stars, mainly from baseball and boxing.
However, Odesnik denied being a client of Bosch and insisted he had already received an apology from the newspaper that reported the allegations.
"On all accounts, that's erroneous. None of that's true," Odesnik said after his 7-6, 4-6, 6-2, 3-6, 7-5 defeat to Taiwan's Jimmy Wang in the Wimbledon first round.
"I don't have any connection to it. I mean, any other question you can ask my lawyer. I had a retraction from the paper already. That's it. This is old news.
"My name was in the papers a lot, and I guess they're trying to tie me to that again. It's erroneous.
"I went through this four years ago. They can keep bringing it up but they're not going to find anything."
Odesnik insisted he had nothing to hide because he has undergone regular drug tests from tennis authorities and WADA, the global doping agency.
"I know this year I've been tested every single month," he said. "I've had an out of competition test on a regular basis, blood and urine, from USADA. The ITF as well, I've been tested by them and WADA.
"I'm giving my whereabouts to three different governing bodies. I've never missed an out of competition test. I've made myself available for all of that.
"I've done nothing wrong. I'm as clean as a whistle. I've never had a positive test."
Claims that Odesnik was effectively informing on his fellow players as a part of the deal to cut his suspension drew an angry response from some stars, including now retired former US Open champion Andy Roddick.
But Odesnik was adamant he still had a good relationship with many of his peers.
"I've never spoken to Andy...I think I have a pretty good relationship with a lot of the players," he said.
"I practise now in Boca at the USTA center with a lot of the American guys. They're helping me as much as they can. I feel it's good."