Russia World Cup hero Denis Cheryshev could be asked to provide anti-doping chiefs with documentary evidence an injection he was given was legal after his own father was quoted saying it contained “growth hormone”.

Investigators from the Russian Anti-Doping Agency (Rusada) were planning to contact all those involved in the treatment of an injury that sidelined Cheryshev last year, one his father Dimitri spoke about during an interview with Russian publication Sport Weekend.

Cheryshev, a star of his country’s shock run to the World Cup quarter-finals, was forced on the eve of Russia’s penalty-shootout win over Spain to deny taking performance-enhancing drugs following the comments attributed to his father.

The Russian Football Union (RFU) later announced the treatment Cheryshev had received had been a perfectly-legal platelet-rich plasma (PRP) injection, accusing the journalist who interviewed his father of having “incorrectly interpreted his words” and adding: “This is confirmed by the recording of the interview.”

Sport Weekend stood by the “growth hormone” quote attributed to the 49-year-old but said it accepted it was never intended or understood to mean actual growth hormone, stating he had also referred in the interview to "growth factor", another term for PRP therapy.

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Cheryshev snr hung up on Friday when contacted by the Telegraph about his Sport Weekend interview, failing to respond to further requests for comment.

The RFU said the course of the player’s treatment, which Cheryshev’s father alleged had been carried out at his club, Villarreal, had been checked by its own medical committee at the time.

Confirming Rusada investigators had already been in contact with that committee, the agency’s deputy director general, Margarita Pakhnotskaya, on Monday told the Daily Telegraph: “They promised to provide everything.”

Asked whether Rusada would request contemporaneous medical records of the injection administered, she replied: “I hope that our investigators start their conversation today by checking if it is recorded.”

She added: “They wanted to speak also to the journalist and probably also to some doctors from the Spanish club if they are available.”

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Two of the biggest sporting scandals in the UK in the past year revolved around the failure to properly record the administering of medication to Sir Bradley Wiggins and Sir Mo Farah.

Wiggins was investigated by UK Anti-Doping over whether he had broken anti-doping rules by taking triamcinolone, rather than - as he has always maintained - fluimicil, before the 2011 Tour de France.

Farah came under scrutiny after Robin Chakraverty - now the doctor for the England football team - failed to record the dosage of L-carnitine given to the four-time Olympic champion before the 2014 London Marathon, which he insisted was within legal limits.

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A report by MPs following a parliamentary inquiry into combating doping in sport was scathing about these twin oversights, calling for the General Medical Council to investigate any incident where a doctor working in sport had failed to record medicines they supply to athletes in their care.

Such a failure does not constitute an anti-doping offence but use of growth hormone without a medical exemption does and is punishable with a ban of up to four years.

The RFU on Monday reiterated Cheryshev’s and its own denials of any wrongdoing, adding it had been given no documents about his injection from the doctors of Villarreal and that questions about them should be directed to the club and the Spanish authorities.

Villarreal did not respond to requests for comment.