The reputation of Lance Armstrong - and possibly the entire sport of professional cycling - hangs on the evidence given by his former US Postal teammate to a US federal investigation into doping accusations against the seven-time Tour de France champion.

And that teammate is not convicted drug cheat and confessed liar, Tyler Hamilton. Nor is it another liar, and cheat-turned-wannabe-whistle-blower, Floyd Landis.

It is George Hincapie, the man who was Armstrong's lieutenant in all seven of his famous victories.

Hincapie has been dragged into this latest round of unproven accusations against Armstrong, following a secondary report on the 60 Minutes website in the US which claimed he had admitted to the federal investigation to using the banned performance-boosting substance EPO alongside Armstrong.

Hincapie has since issued a statement through his lawyers, vehemently denying taking any illegal substances whatsoever. It's hard to imagine a stronger denial.

He is still riding on the professional circuit, and has the most to lose out these accusations (outside Armstrong, of course), if any cast-iron evidence from the Hamilton interview can be found.

One has to question the motives of Hamilton in making these accusations. What has he got to gain from turning on Armstrong? And why now? Why not over the past 10 years since he left Armstrong's US Postal team, particularly after being forced into retirement after copping an eight-year ban for substance abuse?

Perhaps his guilty conscience coincidentally just happened to emerge with the release date of his autobiography. Or is Hamilton trying to claw back some of the reputation he lost throughout his blighted career?

Because right now he has none whatsoever.

In 2004, Hamilton failed a blood transfusion test at the Olympics, after winning the men's time-trial, but a secondary sample couldn't be tested as the Athens lab had frozen the back-up sample, rendering it useless.

Not to worry, as Hamilton would again test positive only three months later in the Vuelta a Espana for an elevated red blood cell count. The same test found contaminants of another person's blood in Hamilton's blood stream, a blatant case of blood transfusion. Hamilton was slapped with a two-year suspension which, of course, he unsuccessfully appealed.

Hamilton returned to cycling in 2007, amid rumours implicating him in the Operation Puerto drug heist, which turned the world of cycling upside down. He would again test positive in April 2009, this time for a banned steroid, and was hit with an eight-year ban which forced him into retirement.

During this time, both Armstrong and Hincapie continued to be tested and continued to return clean results.

It should also be noted that Hamilton never failed a drug test while riding with Armstrong and Hincapie at US Postal. He, and Landis, both returned positive tests while they were riding with the Phonak team.

Hamilton is the latest in the ever-increasing chorus of riders coming out and speaking against Armstrong. But none of these riders have the ‘cleanskin' reputation of ‘gentle' George Hincapie. They all seem to be intent on regaining whatever crumbs of reputation they can salvage.

The doubt surrounding Armstrong does continue to grow. There's a big difference between saying, 'I've never tested positive' and 'I've never taken drugs'. Armstrong refuses to say the latter.

But unless quantifiable evidence can accompany these white-knight accusations, then we should all accept, for the sanctity of cycling at least, that Armstrong has never failed a test and - until proven otherwise - must be regarded as a clean athlete.

Oh, and the only scarce of good news that has come out of Hamilton's accusations? Australia's very own Michael Rogers was awarded a bronze medal from the 2004 Athens Olympics, after Hamilton ‘voluntarily' surrendered his gold medal in the individual time-trial.