Jannik Sinner, the No 1 men’s tennis player, has been found to bear no fault or negligence for two failed anti-doping tests after twice testing positive for the banned substance clostebol in March. An independent tribunal last week determined that Sinner had been contaminated with the substance through his physiotherapist.

Neither of Sinner’s positive anti-doping tests had previously been published. The International Tennis Integrity Agency (ITIA) organisation consulted with scientific experts and then took the case to an independent tribunal headed by Sports Resolutions.

The independent tribunal concluded that Sinner had been contaminated with clostebol through a product his fitness trainer had purchased, which Sinner’s physiotherapist used to treat a cut on his finger. Sinner’s physiotherapist treated the Italian without gloves, meaning the product was inadvertently transferred to Sinner. Clostebol is an anabolic androgenic steroid (AAS) derived from testosterone.

“Jannik has cooperated fully with the ITIA’s investigation from the beginning,” said Sinner’s representatives. “The ITIA is battling misconduct in sport and doping in particular. Its rules and processes are exceptionally rigorous and following forensic investigation and an independent hearing, the independent tribunal have decided that Jannik is innocent. He is not at fault.”

The first positive anti-doping test took place on 10 March during the Indian Wells Masters 1000 event and trace amounts of a metabolite of clostebol were also found in a test eight days later, just before the Miami Open, which Sinner won. His results, points and prize money earned at Indian Wells have been disqualified.

Sinner was notified of the positive test in April. Sinner withdrew from the quarter-finals of the Madrid Open after a three-set win over Karen Khachanov on 30 April, citing a hip injury. He did not compete again for 27 days until his first round match at the French Open after also withdrawing from the Italian Open in Rome, his home tournament.

While athletes receive mandatory provisional suspensions after an anti-doping violation, a provisional suspension can be appealed and removed if an athlete demonstrates at a hearing that the violation likely involved a contaminated product or a substance of abuse. Sinner successfully appealed both provisional suspensions.

Since returning at the French Open, Sinner has continued to compete on the ATP Tour as normal in what has been a breakout season, with the Italian winning his first grand slam title at the Australian Open and rising to No 1 shortly after. Yesterday, Sinner won his second Masters 1000 title at the Cincinnati Open and he boasts a tour-leading 48-5 record this year.

“I will now put this challenging and deeply unfortunate period behind me. I will continue to do everything I can to ensure I continue to comply with the ITIA’s anti-doping programme and I have a team around me that are meticulous in their own compliance.”