Cycling: Armstrong dope probe

Greg LeMond believes a federal probe into fellow Tour de France winner Lance Armstrong could be the downfall of the world's most famous cyclist.

Seven-time champion Armstrong is racing his final Tour amid accusations by ex-teammate Floyd Landis that their former team, US Postal, was involved in systematic doping.

The federal investigation into Landis' claims is led by Jeff Novitzky, whose probe into the Balco doping scandal brought about the fall of athlete Marion Jones.