Cycling star Andy Schleck is confident Lance Armstrong is telling the truth about his drug-free comeback - because he was able to beat the Texan.
The US Anti-Doping Agency said Armstrong's test samples in the 2009-10 Tours de France strongly suggest evidence of doping.
But one of the features of Armstrong's televised confessional was an adamant denial that he doped at all during his comeback.
After retiring in 2005, Armstrong started his high-profile professional cycling comeback at the 2009 Tour Down Under in Adelaide.
He went on to finish third that year at the Tour de France behind winner Alberto Contador of Spain, with Schleck the runner-up.
Armstrong was not a contender at the 2010 Tour de France and retired for good after the 2011 Adelaide race.
Schleck said he did not defend Armstrong for his doping but also believes him about the comeback being clean.
"He made his comeback and he was beaten in the first year by Alberto and me," the Luxembourg rider said of the 2009 Tour de France.
"So in my eyes, I was clean, I know I was always a clean rider and I keep on riding clean.
"So why should he be doped and be behind me?
"I believe in his comeback that he was clean."
Tour Down Under race director Mike Turtur said he could not comment on whether Armstrong rode clean during his three visits to the Australian race.
"I can't say, because I don't know," Turtur said.
"I can't answer a question that is based on speculation - I don't know.
"It's hard to answer that sort of question."
The Adelaide Tour paid Armstrong millions of dollars to race there in 2009-11.
Schleck, defending Tour Down Under champion Simon Gerrans and Belgian world road champion Philippe Gilbert all defended the current generation of riders.
"We're just looking ... to start the season and to finally speak about sport," Gilbert said.
"This is part of the story of cycling, of course, but this is the past and we just want to see something different now."
Gerrans turned pro in 2005 - the year Armstrong won his last Tour de France.
"I've never been exposed to doping in any of the teams I've been involved with, I've never doped," Gerrans said of the sport now.
"In saying that, the fight against doping is an ongoing battle, I don't think the sport will ever be 100 per cent clean.
"I don't think any professional sport will be 100 per cent clean because people cheat - that's human nature."
Indeed, Schleck's brother Frank is currently fighting a doping charge.
Andy Schleck also "won" the 2010 Tour de France retrospectively after Contador lost a long fight against his controversial doping case.