Andy Schleck, who was retroactively awarded the 2010 Tour de France win last year, believed Lance Armstrong when the American said he did not dope after his comeback, the Luxembourger said on Saturday.
Schleck is in South Australia for Sunday's launch of the UCI pro tour season at the Tour Down Under but the last day of preparations was again hijacked by Armstrong's televised confessional with chat show host Oprah Winfrey.
Armstrong finally admitted in the interview that he had cheated his way to seven Tour de France titles by using banned performance enhancing substances, but denied any doping on his return from retirement in 2009.
"I'm confident he was clean there because I beat him and, I mean, he won seven Tours de France," said Schleck, who finished runner up at the Tour de France three times and was handed the 2010 win when Alberto Contador was stripped of the title.
"He cheated in these seven tours but still he won these seven tours," he told a news conference in Adelaide.
"So he still was a good rider and he made his comeback and got beaten the first year by Alberto and me. I know that I always was a clean rider ... so why should he be doped and be behind me? So I believe in his comeback that he was clean."
Orica-Greenedge rider Simon Gerrans, who is defending the Tour Down Under title, said he hoped the culture in cycling had changed and that some of Armstrong's comments had been encouraging in that regard.
"The fight against doping is an ongoing battle. I don't think any sport will ever be one hundred percent clean because people cheat. That's human nature," said the Australian.
"But in saying that, I think one of the positive things that come out of Lance's confession was that he did mention that the biological passport that has been in place now for several years, basically it made it impossible for him to do the things he was doing in the past - to cheat and win the Tour de France.
"So, I think in light of that we are racing in a much, much cleaner sport these days."
Armstrong said in a sometimes emotional second part of the broadcast, which was aired on Saturday in Australia, that the life ban from most organised sport that he had received for his infractions was akin to the "death penalty".
Cycling commentator Phil Liggett, one of many in the sport who were once a staunch supporters of Armstrong, said the tears the American shed when discussing the impact of the lies on his family were probably genuine enough.
What the Briton - the voice of cycling for many in the English-speaking world - did question, however, was Armstrong's motivation for making the admissions.
"I believe the only reason he's come clean, except for the fact that he's been forced to come clean, is that he would love to race again and he'd give anything to do that," he said.
"I don't think at the moment he's done enough to be given a relief on his life sentence, because we need to know names and how he managed to trick five hundred controllers throughout his career."
The Tour Down Under starts with a 51-km circuit race in Adelaide on Sunday and concludes on Jan. 27 after a total distance of 758.5 km over six stages.
Although Armstrong's confession has been the talk of the sporting world for the last two days, many of the riders were keen to put the scandal behind them as they looked forward to getting their season underway.
"I don't think it's important to talk about Armstrong," said BMC rider Philippe Gilbert.
"I think we are just looking forward to starting the season and to finally speaking about sport. This is part of the story of cycling of course, but this is the past and we just want to see something different now."