Eufemiano Fuentes, the medical doctor at the centre of the blood doping ring uncovered in the Spanish Civil Guard's Operación Puerto, has now declared that he would be willing to hand over his list of clients to the World Anti-Doping Agency if asked to do so.

According to a report in Spanish daily El Pais, that list includes 39 athletes, a figure much smaller than what was hypothesized in the media based on the more than 200 blood bags discovered in the raid on Fuentes' Madrid clinic and other locations in 2006.

"If they felt I was useful and they asked me, I would consider it and would be willing. What I don’t know is if what I would give them would be worthwhile to them or not," Fuentes said at yesterday's hearing. "If, within this cooperation such a list was necessary, they would have it."

Together with his sister, Yolanda, and three others Fuentes is on trial in Spain for “crimes against public health” over the doping scheme, and are facing up to two years in prison if found guilty of the offence.

The prosecution has wrapped up its case with yesterday's hearing, but the defence will still present its final arguments on Friday.