Hulk allegation is the latest in a litany of racist incidents in Russian league football over recent years.
The disciplinary commission of the Russian Football Union has opened an inquiry into reports that Brazil forward Hulk was the target of racist abuse at the weekend.
Media reports in Russia claimed that the Zenit St Petersburg star complained about the chants aimed at him during the game against Spartak in Moscow.
Disciplinary chief Artur Grigoryants confirmed that an investigation had been launched after the issue was reported by the match delegate.
This is the latest in a litany of racist incidents in Russian league football over recent years – and which became a particular focus of attention during the country’s successful campaign to win host rights to the 2018 World Cup.
The Hulk incident coincided with the RFU suspending Christopher Samba for two games after the former Queens Park Rangers and Blackburn player was subjected to racist taunts by fans of Torpedo Moscow while playing for Dynamo Moscow the previous Sunday.
Torpedo were handed a partial ground closure for one match while Samba, who was substituted at half-time in apparent distress, was banned for two games for a gesture to Torpedo fans as he left the pitch.
Ivorian defender Dacosta Goore was also banned for two games in Russia for a similar offence last year after showing his middle finger to fans following racist abuse.
In 2008 Zenit were threatened with expulsion from the UEFA Cup after racist abuse aimed by fans at players of Marseille. In 2011 the Brazilian leftback Roberto Carlos, then with Anzhi, walked off the pitch after a banana was thrown at him.
In 2012 Samba, also then playing for Anzhi, was racially abused while playing for Anzhi away to Lokomotiv Moscow. On that occasion, Samba threw the banana back into the stand and did not face any punishment.
In October 2013 CSKA Moscow received a partial ground closure after racist abuse of Manchester City’s Yaya Toure.
The punishment had no effect.
CSKA lost 1-0 to Bayern Munich last night in a totally empty stadium after subsequent misbehaviour of their fans against the Czech club Viktoria Plzen. They are awaiting further disciplinary action from European federation UEFA for fan violence before their opening group defeat by 5-1 at Roma on September 17.