A blood doping expert, Dr Michael Ashenden.says a suggestion by a top cycling official that Lance Armstrong never took illegal drugs is "flabbergasting".
Hein Verbruggen, honorary president of the International Cycling Union, was quoted in the US Anti-Doping Agency's Armstrong report as saying in 2011: "Armstrong has never used doping."
Ashenden, who has been an independent reviewer of blood profiles in cycling since 2008, continued: "For the honorary president of [cycling's governing body] the UCI to say he [Armstrong] hadn't doped, in the face of everything, I really have to question what his motives were to say that."
You have the quotes from Hein Verbruggen saying he was sure [that Armstrong hadn't doped] and I find that absolutely flabbergasting."
Armstrong has been provisionally stripped of the seven Tour de France titles he won between 1999 and 2005 after Usada last week published a report that labelled him a "serial" cheat who led "the most sophisticated, professionalised and successful doping programme that sport has ever seen".
The report followed Armstrong's decision not to contest allegations of doping in August. The removal of his Tour titles and accompanying lifetime ban is still to be ratified by the UCI.
The Usada "reasoned decision" on the Armstrong case quotes Verbruggen as saying in May 2011: "There is nothing. I repeat again: Lance Armstrong has never used doping. Never, never, never.
Ashenden also raised questions about a "triangle" that has been revealed apparently involving Armstrong, the UCI and a drug-testing laboratory in Lausanne, Switzerland, as a result of a payment in excess of $100,000 (£62,200) the American cyclist made to the sport's governing body.
The UCI admitted it accepted a donation from Armstrong in 2002, but strongly denies it was connected to any cover-up of a positive test.
The head of the drug-testing laboratory acknowledges meeting Armstrong at about the same time, while the lab was also allowed by the UCI to use a blood analysing machine for free.
Verbruggen denies making the comments.