The case of disgraced cyclist Jan Ullrich can help identify others involved in a Spanish doping scheme, the head of his former team T-Mobile and Germany's leading sports parliamentarian said on Thursday, according to dpa. T-Mobile head Bob Stapleton and sports politician Peter Danckert also said that Ullrich appears to be the victim of bad advisors in the scheme around suspect doctor Eufemiano Fuentes. A Bonn public prosecutor revealed on Tuesday that DNA samples taken from blood bags seized from Fuentes in a Spanish doping probe "without any doubt" belonged to the 1997 Tour de France winner Ullrich. A saliva specimen from Ullrich was compared with the blood samples from Spain. Ullrich's lawyers said that the test result was no evidence of a doping offence and even suggested manipulation. Ullrich, who retired in February after being fired by T-Mobile last year after he was linked with the affair, has protested his innocence throughout. Stapleton told the cyclingnews website it would be "a travesty" if Ullrich is the only rider punished over the case in which more than 50 riders are reportedly involved. "This is another wake up call for the sport. It is further, scientific proof that athletes were involved and that this is a major, major doping ring with in the sport. It can't just be that a single guy bears the full weight of this on his shoulders and that there is no other action taken across the sport," he said. Danckert expects the "existing doping cartel" to be revealed sooner or later and aims to combat every aspect of substance abuse. "There is no plausible reason that four and a half litires of blood in different bags were found with the Spanish doctor. Jan Ullrich did not let blood himself, it was doctors who did that. That's why we must find out who is responsible," said Danckert. Danckert on Wednesday called for a hearing before parliament's sports commission in May, to which Ullrich and team doctors and officials are to be invited. Danckert has offered to meet Ullrich, hoping that the former star realises that he can help tackle the problem and partly correct his image. "Through bad advisors he has manoeuvred himself into a situation which can become more and more critical," said Danckert. Stapleton agreed: "I prefer to remember Jan as an outstanding bike rider that made some mistakes. To see him advised in this unusual and increasingly unrealistic public position is really painful."