In the wake of Lance Armstrong's doping admissions, five defendants are due to be cross-examined in a Madrid courtroom in connection with a sophisticated blood doping network uncovered by police seven years ago.
The alleged ringleader, Dr. Eufemiano Fuentes, was in court Monday, but judge Julia Santamaria only reviewed legal details with lawyers before deciding to leave testimony until Tuesday.
The trial is limited to doping in cycling, even though athletes in other sports were also reportedly implicated in the discovery of blood bags and other doping equipment in 2006. The World Anti-Doping Agency has pushed for all the evidence to be released.
Lawyer Carlos Sanchez, representing former cyclist Jesus Manzano, one of the plaintiffs in the case, said the opening day was taken up "presenting individual allegations and pertinent defences" to determine what arguments could be used in the trial.
The much-delayed trial, in which 35 witnesses are expected to testify, is due to last until March 22. It has sparked great media interest and the courthouse was surrounded by journalists, photographers and TV cameras from early Monday morning.
Santamaria can only rule on matters covered by Spanish law as it applied in May 2006, when police raids uncovered a mass of blood doping evidence in labs, offices and apartments. The case will focus on whether public health was endangered at any point.
Fuentes allegedly stored bags containing high concentrations of hemoglobin-rich red cells taken from the riders' own blood so it could be re-injected in competition when they needed a performance boost.
Manzano is a retired cyclist who turned whistleblower after suffering medical problems he said were caused by the doping practices while riding for team Kelme.
"Manzano had to stop being a professional cyclist as a result of these practices," Sanchez said.
Speaking to reporters outside the courthouse, Sanchez said the trial must determine whether the blood extractions, transfusions, storage and transport and the labeling of human plasma and blood could have represented a health risk.
"First there is the question of storage," Sanchez said. "Blood must be preserved only in specialized centres. What you can't have is blood being stored at home in the fridge."
Also on trial are Fuentes' sister and fellow doctor Yolanda; Manolo Saiz, a former ONCE and Liberty Seguros team sports director; and Vicente Belda and Ignacio Labarta, both associated with the former Kelme team.
Jose Luis Merino, another medical doctor, also was also due to be tried, but Santamaria granted him a temporary stay last week after he presented medical reports stating that he is suffering from Alzheimer's.
Although no riders will sit in the dock, many will be called to testify as witnesses, including two-time Tour de France champion Alberto Contador. He was stripped of a third Tour title after testing positive for clenbuterol.
Cyclists themselves will not be on trial because of the legal limitations of the case, but there is great interest in case other sports — such as football and tennis — get mentioned as evidence is given.
Several hundred blood and plasma bags were seized by police but the Puerto case has only implicated just over 50 cyclists — including Contador, Ivan Basso, Jan Ullrich and Alejandro Valverde.