Italian Francesco De Bonis became the first cyclist to be given a doping ban because of discrepancies in his biological passport.
Unlike conventional tests, which can detect the presence of a banned substance, the biological passport monitors swings in blood parameters that may indicate manipulation.
The ground-breaking biological passport system, which was pioneered by cycling's world governing body UCI in 2008, may become a strong weapon to catch drug cheats even if they have never been tested positive.