US Olympic gold medal-winning cyclist Tyler Hamilton has been banned for two years for blood doping, the US Anti- Doping Agency announced on Monday.
Hamilton’s ban stems from a positive test for blood doping at the Tour of Spain on September 11, 2004, and he forfeits all competitive results from that date, USADA said.
Hamilton had also tested positive for blood doping after winning time-trial gold at the Athens Olympics, but the "B" sample for that test was destroyed when it was frozen.
The International Olympic Committee had already ruled that it could not strip Hamilton of his medal without a viable B sample as a back-up test.
Hamilton had protested his innocence in both instances and took his case to the Court of Arbitration for Sport (CAS).
"Following the full evidentiary hearing, the majority of the AAA/CAS Panel directly rejected Hamiltons defenses and found that his positive sample was ’due to a homologous blood transfusion,’" USADA said in a statement.
"Based on blood screens taken in the spring and summer of 2004, the International Cycling Union (UCI) warned Hamilton and his team that Hamilton was suspected of manipulating his blood," USADA said. "Following these warnings, UCI target-tested Hamilton and he tested positive."
Blood doping is a means of enhancing endurance by increasing the amount of oxygen-carrying red blood cells using one’s own blood or a donor of the same group. (AFP)