Four-time Tour of Spain cycling champion Roberto Heras of Spain faces a two-year ban from competition after testing positive for performance-enhancing drugs.

Spanish authorities re-tested his "B" sample after the first test proved inconclusive. This time the test was positive for the endurance-boosting drug EPO.

Heras said at a news conference in Madrid Friday that he has never doped himself. He said that he cannot allow his sacrifices to be trampled because of an error.

The Liberty Seguros team suspended Heras this month after the International Cycling Union said he tested positive during the penultimate leg of this year's Tour of Spain.

Heras could be stripped of this year's Tour of Spain title and runner-up Denis Menchov would be declared the winner.

Some information for this report provided by AFP and AP.