Spanish cyclist Moises Duenas Nevado's backup sample from the Tour de France has come back positive for the banned blood-booster EPO.
|Ricardo Ricco also tested positive for blood booster erythropoietin (EPO) during the Tour [GALLO/GETTY]
Pierre Bordry, the head of the French anti-doping agency, said the "B" sample confirmed the original "A" sample finding.
Duenas Nevado, who has denied doping, faces a two-year ban if found guilty.
Bordry said other tests from the Tour showed suspicious signs of a third-generation EPO.
Several Tour de France riders are having their blood samples retested for traces of the banned blood booster EPO.
Bordry said that the testing involved riders who were already under scrutiny for suspicious urine samples.
He declined to name the cyclists.
The new blood tests will look for CERA, a third-generation variation of EPO.
Italian rider Riccardo Ricco tested positive for the substance during the Tour.
"I have decided that we will retest, with blood testing, all those who showed up as suspicious during the urine samples," Bordry said.
"When we did the urine samples of those athletes, we had a serious suspicion that there was CERA.
The laboratory could not say definitively.
The same analysis will be done, but in the blood samples."
Bordry asked for the blood samples to be sent from Lausanne, Switzerland, where they were tested during the Tour.
"All the blood tests have been repatriated to France," Bordry said, adding that they are currently being examined at the Chatenay-Malabry laboratory, outside Paris.
Testing has already begun and could take up to two weeks, Bordry said.
Duenas Nevado was 19th in the overall Tour standings after 10 stages when he was informed of his positive test by authorities at the hotel of his Barloworld team in the southwestern town of Tarbes.
Bordry said Duenas Nevado tested positive after the fourth stage on July 8 in Cholet, the site of the race's first time trial.
He was immediately suspended by his team and thrown out of the race.
A police search of his room found medical materials like syringes, needles and medical drip bags.
South African industrial conglomerate Barloworld later announced it would not be renewing its sponsorship of the team, one of several sponsors to quit cycling.
For the third straight year, the Tour was wracked by doping cases.
Manuel Beltran of Spain also tested positive for EPO, and Dmitriy Fofonov of
Kazakhstan tested positive for a banned stimulant.
The Tour de France 2008 was won by Carlos Sastre with Team CSC Saxo Bank.