Russian club FC Rostov are likely to face a UEFA disciplinary case for fan racism after a banana was thrown onto the field during their Champions League game against PSV Eindhoven.
The FARE Network, which monitors racist incidents for UEFA, said the banana was thrown about eight minutes into Wednesday's 2-2 draw and remained on the field for at least 15 minutes.
The game was already being played in a partially closed stadium after UEFA sanctioned Rostov for fan racism at a home game against Ajax in August.
"We have reviewed the media from the match and have seen that it took place in the eighth minute after Rostov scored and took place in the opposite end to the action," said FARE director Piara Powar.
"A supplementary report to UEFA will follow from us this morning [Thursday]."
Vyacheslav Koloskov, the Russian Football Union's honorary president, said the incident could tarnish Russia's image as it prepares to host the World Cup in 2018, with Rostov-on-Don due to host games during the tournament.
"This banana could cost us heavily," he said. "It's not to be tolerated at any time, especially now. Rostov may be forced to play a game behind closed doors."
But Alexei Sorokin, the head of Russia's World Cup organising committee, sought to play down the incident.
"I think the incident in Rostov is unique and that this will not repeat itself in the future," he said.
"We follow this issue along with the Russian Football Union but it is obviously impossible to screen every person in the stands."
Non-white players, including former Brazil defender Roberto Carlos, have been taunted with bananas during Russian league games in recent years.
Champions League games have also seen racist incidents involving Russian fans, with current league champions CSKA Moscow repeatedly punished by UEFA for offences including monkey chants aimed at opposition players.
In 2014, then-Rostov coach Igor Gamula was suspended by Russian soccer authorities for derogatory comments about black players on his team.
Following protests by Rostov's players, he was removed from his post and given a role with the youth team, where he remains.
The most recent research from FARE and the Moscow-based SOVA Center reported a surge in the number of racist displays by Russian soccer fans, with most cases going unpunished.
Researchers logged 92 incidents of discriminatory displays and chants by Russian fans in and around stadiums in the 2014-15 season, compared to 83 for the previous two seasons combined.
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