An anti-doping case has been opened against Russian medal-winning curler Alexander Krushelnitsky, says the Court of Arbitration for Sport.

Meldonium is a drug designed to treat ischemia, a condition where there is a reduction in blood supply to body tissue. It is also said to have benefits for diabetes sufferers.

Curling has long been recognised as a deceptively strenuous sport with huge financial rewards for competitors who are in the gym enduring rigorous six-hour workouts every day. Medal winners are revered as heroes by their legion of followers. The temptation to take improvement-enhancing drugs is the scourge of the sport.