Astana Team Chief Summoned Over Doping

Astana manager Marc Biver has been summoned by ProTour authorities to explain the three doping tests recently failed by some of the cycling team's most prominent riders.

The International Cycling Union (UCI) said in a statement on Friday Biver would be heard by UCI ProTour Council president Vittorio Adorni "to explain this disturbing situation".

Germany's Matthias Kessler tested positive for testosterone before the Tour de France, while Kazakhs Alexander Vinokourov and Andrey Kashechkin both failed tests for blood transfusions.

Pre-race favourite Vinokourov's test took place after his victory in a Tour de France time trial in Albi while Kashechkin was random tested in training in Turkey on Aug. 1.

Both Kessler and Vinokourov were sacked after their B samples also proved positive while Kashechkin is awaiting tests on the second sample and will also be dismissed should it confirm the first.

Biver was not immediately available for comment but Astana said on Thursday Kashechkin's test again "hampered the team's credibility".

"This new blow only reinforces the team leaders' will to take drastic measures for a healthy cycling," the team added in a statement.

The Swiss-based Kazakh team decided to take a break and not participate in any race for a month to ponder the future while major team sponsors are all reviewing their involvement in the sport after a dope-ridden Tour de France last month.

German teams T-Mobile and Milram announced this week they were continuing to race despite the current problems.

The UCI welcomed their decision "to continue their commitment to cycling despite difficult times for the sport in Germany recently".

German hopeful Linus Gerdemann, seen as the future of the sport in his country after he held the Tour leader's jersey for one day, also welcomed the news.

"It's an enormous relief, especially if you take into account the past events and the succession of doping cases," Gerdemann said.

"T-Mobile has sent an important signal for cycling, but also for professional sport in general."