PYEONGCHANG (South Korea) • A Russian medallist at the Pyeongchang Winter Olympics is suspected of having tested positive for a banned substance, a source at the Games said yesterday, in a potential major blow to Russia's efforts to emerge from a drug-cheating scandal.

Alexander Krushelnitsky, a bronze medallist along with his wife in mixed-doubles curling, is suspected of having tested positive for meldonium, the source said.

Meldonium - the same substance that saw tennis star Maria Sharapova serve a 15-month ban - increases blood flow and improves exercise capacity in athletes.

Krushelnitsky did not respond immediately to a request for comment. A spokesman for the Russian delegation at Pyeongchang said he had no immediate comment.

Russia has been accused of running a state-backed, systematic doping programme for years, an allegation Moscow denies.

A fresh doping case would be deeply embarrassing for Russia, which has 168 athletes deemed clean competing in Pyeongchang as neutral Olympic Athletes from Russia (OAR). All those athletes met stringent International Olympic Committee (IOC) criteria and underwent a rigorous testing regimen to feature in South Korea.

Russian sports officials are to meet anti-doping officers at Pyeongchang, the source said, adding that any violation would only be confirmed after analysis of a "B" sample.

Krushelnitsky and his wife, Anastasia Bryzgalova, won bronze in a play-off against Norway, which would take that medal if a doping violation were to be confirmed.

"I hope it's not true... for the sport of curling," said Norwegian team skipper Thomas Ulsrud. "If it's true I feel really sad for the Norwegian team who worked really hard and ended up in fourth place. They just left for Norway and they aren't even here."

The IOC said it had taken note of the case without going into details.

It said that if the case were to be confirmed, it would be considered by its OAR Implementation panel, the body in charge of monitoring the OAR team's behaviour at the Games.

"On the one hand, it is extremely disappointing when prohibited substances might have been used but, on the other hand, it shows the effectiveness of the anti-doping system at the Games which protects the rights of all the clean athletes," an IOC spokesman said.

The IOC suspended Russia in December after revelations of a widespread and highly orchestrated doping conspiracy, which first emerged before the Rio 2016 Summer Games.

REUTERS, AGENCE FRANCE-PRESSE