MADRID (AFP) - American cyclist Tyler Hamilton, who won the Olympic time trial gold medal last month, faces a two-year ban after becoming the first ever athlete to give a positive test for blood doping.
The 33-year-old tested positive after winning the Tour of Spain's eighth stage time trial on September 11 and he pulled out of the Tour six days later.
Hamilton's Swiss Phonak team confirmed the postive result and news of the second sample is expected within 48 hours.
Phonak sporting director Alvaro Pino said he was confident about Hamilton's innocence. Live on Spanish television while driving a car during the 16th stage of the Tour of Spain, Pino said: "Last night (Monday), he (Hamilton) said 'you can sleep soundly.'
"I believe him. He is an intelligent guy who would not take the risk of having a blood transfusion. The test result is not yet conclusive. I can't tell you any more. Tyler is set to give a press conference with the team in Zurich at 6p.m. (1600 GMT)."
The UCI has for the first time used a method to detect blood-doping which has been used in legal medicine for paternity tests. The tests were developed in Sydney and are now used by two accredited laboratories in Athens and Lausanne, Switzerland.
The test can identify different groups of red blood cells which thereby determines conclusively whether blood-doping has taken place.
Usually an athlete will withdraw blood before reintroducing it before an event to increase oxygen-carrying capacity to the muscles hence enhancing his performance.
Till now blood doping, suspected of being used in athletics for the last 30 years, was undetectable.
Hamilton has had an eventful, up-and-down year, injuring his back in a crash which led to his retirement during the 13th stage of the Tour de France in July but bounced back to win the time-trial in Athens.
Hamilton famously raced three weeks to finish fourth in the 2003 Tour de France after breaking his collarbone in the first stage.
If Hamilton is eventually disqualified from the Olympics, gold would go to Russia's Viatcheslav Ekimov, also the champion in Sydney four years ago, the silver to American Bobby Julich and the bronze to 2003 world champion Michael Rogers of Australia, who was crowned after the disqualification through doping of original winner David Millar of Britain.
Hamilton has for some time been in the shadow of six-time Tour de France winner Lance Armstrong, whom he served in the US Postal team till 2001. He still keeps in regular touch with Armstrong and for much of the European season they live in the same building in the north eastern Spanish city of Gerona.
Hamilton dominated the Tour of Romandy this year to such an extent he was considered among an elite group of riders as a possible Tour de France champion.
However his Tour challenge faltered following a fall at Angers and his morale suffered further following the death of his dog.
For Phonak, it was the second doping affair to hit them during the year following the positive test for blood-boosting drug EPO by Switzerland's Oscar Camenzind.
Camenzind was axed by the team and he retired from the sport before being suspended by the Swiss Olympic committee for two years.