New York - Lance Armstrong took notice of Chris Froome's big day at the Tour de France and provoked some quick reaction on Twitter when he raised a hypothetical question about cheating.
Froome and Sky team-mate Richie Porte dominated the Pyrenees mountain stage, prompting Armstrong to post a series of tweets: "Getting lots of questions regarding today's first mountain stage..." and "Clearly Froome/Porte/Sky are very strong. Too strong to be clean? Don't ask me, I have no clue."
It was a provocative question from a rider whose domination of the Tour de France from 1999-2005 was wiped from the record books for using performance-enhancing drugs in each victory. Critics swiftly noted his past cheating.
"I'm not accusing anyone," Armstrong quickly responded. "In fact, quite the opposite. I'm not interested (nor do I have the credibility) to opine there."
Froome, the 2013 Tour champion, holds the yellow jersey as race leader. Like Armstrong in his heyday, Froome left several top rivals behind in the key mountain stage.