Hamburg  - An appeal by banned five-time Olympic speed skating champion Claudia Pechstein will not be decided before autumn in what is expected to be "a battle of experts," a judge at the Court of Arbitration for Sport said on Monday.

Speaking on the condition of anonymity, the judge told the German Press Agency dpa that there was no urgency in the case of blood doping.

The ruling skating body ISU announced on Friday that it banned Pechstein for two years over abnormal blood values and changes of blood values at several tests, most notably at the allround world championships in February in Norway.

Pechstein, 37, is believed to be the first athlete banned over data gathered in a biological passport. The ISU introduced the screening method in 1999 and suspicious results can be sanctioned as a doping offence since this year.

Pechstein has protested her innocence in the case centring on been abnormally high levels of reticulocytes (immature red blood cells) in her blood.

"This is about highly technical questions. I expect a lively debate," said the CAS judge.

The judge said that Pechstein must explain the abnormal blood values while the ISU must cement its ruling with facts.

Looking at the time frame, the judge said that a decision is unlikely to come before autumn, "and only if all sides cooperate.

"An urgent motion will hardly have success because there is no urgency in the case," he said.

Pechstein plans to compete in her sixth Winter Olympics next February in Vancouver, for which she now needs a successful appeal before CAS. She is banned by the ISU from February 9, 2009 to February 9, 2011.

Pechstein is Germany's best-decorated winter Olympian with five gold, two silver and two bronze medals 1992-2006.(dpa)