Spain's anti-doping agency said Thursday it has closed its probe into Valencia's Russian striker Denis Cheryshev, one of the revelations of the 2018 World Cup, after it found no evidence he used a banned substance.

The investigation stemmed from an interview which the player's father, Dmitri Cheryshev, gave to Russian publication Sport Weekend in June 2017 in which he said his son had received growth hormone injections when he played at Spanish side Villarreal.

Cheryshev, 27, shared a letter from Spain's anti-doping agency on his official Twitter account which said that "an investigation was carried out and closed after no signs of irregular conduct were found."

Contacted by AFP, a spokesman for the agency confirmed they sent the letter.

Cheryshev, who scored four goals in five World Cup games for Russia as they reached the quarter finals, had denied any wrongdoing. His father said his statements had been twisted by reporters.

Without a medical exemption, the use of growth hormones is considered doping and is punishable with a ban of up to four years.

Cheryshev joined Valencia in August on a season-long loan from Villarreal.