The Russian track and field federation says Olympic discus silver medalist Darya Pishchalnikova has been banned for 10 years for doping and will be stripped of her medal.
The ban annuls Pishchalnikova's results from May 20, 2012, including her silver medal from last year's London Olympics.
The 27-year-old Russian tested positive for the banned substance Oxandrolone in a retest 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.
Because of the ban, Li Yanfeng of China stands to move up to silver and Yarelys Barrios of Cuba to bronze.
Pishchalnikova previously served a two-year ban from 2007-09.