A player selected on Russia's provisional squad for their home FIFA World Cup beginning this month was part of a doping programme orchestrated by Grigory Rodchenkov, according to the former Moscow Laboratory director turned whistleblower.
Speaking at the launch event of the Foundation for Sports Integrity via videolink, and with his face hidden by a balaclava, Rodchenkov said he recognised one name on the list of 34 players whose positive tests he helped cover up.
FIFA last month concluded an investigation into all 34 players allegedly involved after claiming there was "insufficient evidence".
It prompted Jim Walden, Rodchenkov's lawyer, to accuse world football's governing body of being the latest of many international sports organisations to be "sweeping Russia's doping fraud under the carpet".
Investigations of Russian footballers not in the World Cup squad are "still ongoing", however, with further updates to be provided "in due course".
"There were 34 footballers listed in the doping control programme, playing at junior, under-23, ladies and senior levels," said Rodchenkov.
"It's very important that they are still being investigated because we had initial tests but then the procedure was stopped and reported negative."
Rodchenkov, who remains in witness protection in the United States after fleeing Russia because of concerns over his safety, added that former Russian Football Union (RFU) President Vitaly Mutko told him "not to touch football players".
The Russian Deputy Prime Minister, banned from the Olympic Games for life for his role in the "systematic manipulation of the anti-doping process at Sochi 2014, allegedly told Rodchenkov: "We don't need any positive cases or even noise in football, especially in the national level team".
In a documentary aired by German broadcaster ARD last month, Rodchenkov claimed positive tests in Russian football were ordered to be ignored.
Football was among dozens of sports implicated in evidence of sample tampering at the Moscow Laboratory, which was disclosed in the World Anti-Doping Agency (WADA)-commissioned McLaren Report following evidence from Rodchenkov.
FIFA claims to have assessed all information and evidence contained in the McLaren Report, with the support of scientific and legal experts.
This included Rodchenkov and Canadian lawyer Richard McLaren.
It also claims to have re-analysed "samples taken by FIFA and the Confederations that had been stored at WADA-accredited laboratories, of all players mentioned in the McLaren Reports and high-level players".
All supposedly returned negative results.
Samples "seized" by WADA from the Moscow Laboratory and stored at the Lausanne Laboratory were re-analysed for prohibited substances and have also returned negative results.