Belarus international striker Sergei Kornilenko, who plays for Russian top flight side Samara, has tested positive for the banned substance pseudoephedrine, local media reported on Friday.
Russian Football Union (RFU) president Sergei Fursenkno was quoted as saying: "The sample, which Kornilenko provided after his team's Russian league match against Spartak Nalchik, contained traces of the banned substance pseudoephedrine.
"The case will be forwarded to the national anti-doping agency RusAda."
Fursenko indicated that Kornilenko may have ingested the drug, which is often found in cold remedies, by accident.
"As far as I know there was no malicious intent from the player's side and I believe the penalty should not be severe," he added.
According to FIFA regulations players who break anti-doping rules a first time can be handed bans from six month to two years.