A Russia player is under investigation by FIFA for doping, according to the Russian government.
Russian deputy prime minister Vitaly Mutko, overseeing the government's World Cup preparations, told state news agency Tass he had been informed that FIFA is investigating Rubin Kazan defender Ruslan Kambolov.
Kambolov has played twice for Russia, once in 2015 and once in a friendly against Chile last June. Mutko said the case was "not linked to the national team."
There is also a FIFA investigation into Ivan Knyazev, a former defender with the Russia under-21 team, Mutko said.
He added that both players "have given evidence and we'll see where it goes."
Asked about the Kambolov and Knyazev cases, FIFA said it "cannot comment on whether or not investigations are under way in relation to specific individuals."