MOSCOW (AP) -- Russia's Darya Pishchalnikova could be stripped of her silver medal in the discus at the London Olympics and face a lifetime ban following a positive doping test.

Russia's All Sports agency says Pishchalnikova tested positive for the banned substance Oxandrolone in a reanalysis of a sample taken in an out-of-competition control last May. The original test was negative, but her sample was checked again months later based on a more advanced testing method introduced by the World Anti-Doping Agency.

The positive test means Pishchalnikova could be retroactively disqualified from the London Games, where she finished second behind Croatia's Sandra Perkovic.

If the Russian is stripped of her medal, the silver will go to Li Yanfeng of China and the bronze to Cuba's Yareli Barriosnikova.

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