African players at Russian club FC Rostov want coach Igor Gamula out over allegedly making racist comments.
Asked about Rostov signing a Cameroon player, Gamula apparently told Russian media the club had "enough dark-skinned players, we've got six of the things".
As a result, players including South Africa international Siyanda Xulu are demanding his dismissal.
Gamula told Russian agency Tass: "I've never divided players into good or bad, foreigners or Russians."
He added he had apologised to the team.
Xulu is one of five African players in the squad, with the others emanating from Angola, Mali, Gabon and Ivory Coast.
"People around the world are absolutely disgusted," Xulu's agent Paul Mitchell told BBC World Service.
"We just hope that Rostov as a club will make the necessary recommendations and in our view should get rid of the coach.
"I spoke with Siyanda this morning and I also spoke to the club. The intention was to meet with the president and get this situation sorted out, but not to train under this current coach.
"We've got to stand together and stamp racism out of football."
Gamula told Tass that all players had taken part in training on Monday, adding: "I was deeply worried and didn't sleep for two days. I hadn't wanted to insult or upset anyone.''
Rostov won the Russian Cup last season, but are struggling this season, lying 14th in the Russian league.
Rostov is one of the host cities for the 2018 World Cup.