Monday 21 March 2016 08:06, UK
Russian 400m runner Nadezhda Kotlyarova has tested positive for meldonium, according to TASS news agency.
The substance has been banned by the World Anti-Doping Agency since January 1 this year, with Kotlyarova the first Russian track-and-field athlete to test positive for meldonium since then.
Kotlyarova told Russia's Tass agency that she failed a drug test at last month's Russian indoor championships in Moscow and protested her innocence.
She said the spate of positive tests for the endurance-boosting meldonium is "injustice," and added that she intended "to see this situation out to the end".
Earlier this month tennis player Maria Sharapova revealed she had tested positive for meldonium at the Australian Open in January.
The Russian, who is the women's world No 7, has been provisionally suspended but said she had taken the drug for 10 years on medical advice and blamed her failure to read an updated list of prohibited substances for the failed test.
Russia's athletics federation is racing against time to meet anti-doping standards dictated by the sport's world governing body and have a cheating ban repealed in time for the Rio Olympics in August.
