Russian heavyweight boxer Alexander Povetkin registered a sixth-round knockout to beat France's Johann Duhaupas in a non-title 10-round fight here.
Earlier on Saturday, reports emerged that Povetkin has tested positive for a banned substance, reports Tass.
The Russian pugilist's blood sample dated December 6 contained Ostarine.
Ostarine is a SARM substance, which athletes use during training. It builds up endurance, like anabolic steroids.
The World Anti-Doping Agency (WADA) put SARM substances on its prohibited items list in 2008.
--IANS
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