Lance Armstrong accepted a gift on stage and thanked the cheering fans for an "unbelievable event."

But after finishing 67th Sunday in what he says is his final race outside the United States, Armstrong again had nothing to say about the latest round of drug allegations.

The seven-time Tour de France champion rode in the back half of the main pack for most of the last stage of the Tour Down Under. He crossed the line as the 103rd rider and wound up more than six minutes behind overall winner Cameron Meyer.

Armstrong brushed past reporters without addressing questions raised by Sports Illustrated - a matter he has refused to discuss all week.

His exit from international cycling comes amid comments by his former mechanic Mike Adams, who told a New Zealand newspaper that a U.S. federal investigation into Armstrong's alleged involvement in doping could make him a "symbol for decades of corruption" in the sport.

Adams was cited in the SI article and said he has spoken with Jeff Novitzky, the Food and Drug Administration agent who is investigating this case.

Adams accused Armstrong and his associates of consistently misrepresenting their record on banned drugs. The 39-year-old Texan has repeatedly denied using such substances.

"We hear the same lies over and over again and they become truth," Adams told the Sunday Star-Times.

Adams contends he once found a box labeled "Andro" in Armstrong's house - a term used to describe androstenedione, a banned steroid.

"To be honest when I finally realized what was going on it was very troubling to me because Lance was my friend," Adams said. "When I had my hand forced and had to say 'I know what's going on' it was like telling a bunch of kids there's no such thing as Santa Claus."

The investigation doesn't seem to have diminished Armstrong's popularity with the 110,000 people who lined the street circuit in downtown Adelaide. After he was lauded on stage, Armstrong paid tribute to the fans. He used this race for his comeback to road cycling in 2009.

"I congratulate you all on building an unbelievable event," Armstrong said. "We travel all over the world and you do not see crowds or an atmosphere like this in many places. This rivals the Tour (de France), this rivals the Giro (d'Italia), this rivals the big races. You should know that you made that."

He then was driven away in a team car. Armstrong's only comment this week to the SI article, which examines allegations new and old of his connection with doping, came on Twitter on Friday. He said he expects to be vindicated by the U.S. Anti-Doping Agency.

On Sunday, he tweeted that the Tour Down Under "is done. Thanks to everyone for coming out and supporting such a great race. Adelaide, we're gonna miss ya."