FIFA says there is "insufficient evidence'' to open anti-doping proceedings against any player in Russia's World Cup squad after concluding an investigation launched following the exposure of systemic drug use in Russian sport.
Football's world governing body on Tuesday announced an end to the investigation which followed the McLaren reports, which found state-sponsored doping in Russian sport, including football.
The world governing body said: "FIFA can today confirm that the investigations concerning all Russian players named for the provisional squad of the FIFA World Cup in Russia have been completed, with the result that insufficient evidence was found to assert an anti-doping rule violation.''
Lawyer Richard McLaren's findings were published in December 2016, after a preliminary announcement prior to the Rio Olympics in July 2016.
The McLaren report concluded over 1000 athletes across 30 sports benefited from state-sponsored doping between 2012 and 2015, with the deception's height coming at the Sochi 2014 Winter Olympics.
The implication of 33 unnamed footballers in the McLaren report prompted FIFA to act, prioritising "high-level players against whom a suspicion had been raised,'' in particular those playing at this summer's World Cup. FIFA said none of the players investigated can be named under the World Anti-Doping Agency (WADA) code.
The tournament takes place in Russia next month, with the hosts playing Saudi Arabia in the opening game on June 14 in Moscow.
Investigations involving "several players'' not involved in the World Cup are still ongoing, FIFA said.
FIFA says it has informed WADA of its conclusions and "WADA in turn has agreed with FIFA's decision to close the cases."
The investigation included analysis by scientific and legal experts, reanalysis of stored samples -- the returned results were all negative -- and testing for tampering of samples. There was no evidence of tampering, FIFA said.
FIFA also corresponded with Dr. Grigory Rodchenkov, the Russian scientist turned whistleblower who exposed the full scale of the scandal.
And unannounced target tests were carried out. FIFA said the Russian squad "has been one of the most tested teams prior to the FIFA World Cup."