Leading Spanish cyclist Aitor Gonzalez has been given a two-year doping ban by the Court of Arbitration for Sport.
Gonzalez beat Roberto Heras to win the Tour of Spain in 2002
It ruled that Gonzalez was at fault for taking a food supplement which led to a positive test for a banned steroid at last year's Tour of Spain.
The Spanish cycling federation had fined the 31-year-old in May but the sport's governing body, the UCI, appealed against the decision with CAS.
The ban will apply from 28 September 2005, when Gonzalez stopped competing.
Gonzalez, who won the Tour of Spain in 2002 and the Tour of Switzerland in 2005, tested positive for methyltestosterone during the Vuelta last year and during an earlier out-of-competition test in August 2005.
But he escaped a ban from the Spanish cycling federation after presenting a research report which said the food supplement had been contaminated.
However, a CAS statement said: "The CAS arbitrators have admitted the facts presented by Aitor Gonzalez.
"But the arbitrators have considered that he did not act without fault or negligence in using a doubtful food supplement, prescribed by an occasional doctor and purchased in a fitness centre.
"The athlete could not ignore the risks related to such an ingestion taking into account the repeated warnings given in this regard by the sports authorities."
There were unconfirmed reports at the start of December that the Euskaltel rider had retired from the sport.