The UCI has now announced that he also failed an out-of-competition control taken on 21 February 2012, after a further reanalysis "carried out in accordance with new WADA technical documents concerning the identification of EPO."
It is likely the same testing procedure and the ability to spot EPO use for longer in urine samples lead to the positive test of both Vini Fantini riders Danilo Di Luca and Mauro Santambrogio.
The UCI has not said if it is carrying out any other special re-analysis of samples from the past.
Serebryakov turned professional for Team Type 1 last year and won 11 races in a highly successful debut season, including the Philadelphia International Championship. He was signed by the Euskaltel-Euskadi team for 2013 as they scrambled for UCI points to secure a place in the WorldTour. The Basque team immediately fired him after the first test and the rider claimed he had acted alone.
Serebryakov has already been temporarily suspended after his first positive test and will now face further disciplinary action.
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Stephen is one of the most experienced members of the Cyclingnews team, having reported on professional cycling since 1994. Before becoming Editor-at-large, he was Head of News at Cyclingnews. He has previously worked for Shift Active Media, Reuters and Cycling Weekly. He is a member of the Board of the Association Internationale des Journalistes du Cyclisme (AIJC).
