The World Anti-Doping Agency ordered Moscow's drug-testing laboratory to be shut down again Wednesday.
That followed WADA's finding last month that data stored at the lab was tampered with in an apparent bid to cover up past drug use by Russian athletes and implicate WADA witnesses.
The laboratory was stopped from carrying out most drug testing in 2015 when cover-ups were first suspected, but it was allowed to resume limited blood testing in May 2016.
Figures given by WADA last year show the Moscow lab handled a total of 3,539 samples from 2016 through 2018, including from foreign tennis players. That was a fraction of its previous workload.
The lab's work was focused on the so-called biological passport, a program which analyzes blood for the effects of banned substances, not the substances themselves. WADA said this analysis would be hard to fake.
“It is practically impossible for laboratories to interfere with the blood variables of samples due to the nature of the analytical equipment and the (biological passport) principles in place,” WADA said Wednesday.
WADA said the suspension was agreed by its new president Witold Banka on Tuesday. The lab can analyze any samples it received before then, but would have to send others to different labs.
Some doping substances can only be detected in blood samples, but blood decays rapidly and must be brought to a lab quickly. Without a lab in Moscow, it could be hard to carry out blood testing in some remote areas.
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