R-Sport did not say how it had heard about Elistratov's test but quoted Kulizhnikov's father Alexander as saying his son had learned about his positive result "a few days ago".
"Pasha (Pavel) had no reason to take the illegal drug, he was the best anyway," Alexander Kulizhnikov said.
Reuters could not immediately verify the information.
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On Monday, Russian tennis star Maria Sharapova revealed that she had tested positive for meldonium, a substance that the World Anti-Doping Agency (WADA) banned as of Jan. 1.
(Reporting by Lidia Kelly; Editing by Kevin Liffey)
