Italian world No 1 Jannik Sinner has escaped a ban for failing two anti-doping tests, after a tribunal accepted that the contamination occurred during a massage from his physiotherapist.

The International Tennis Integrity Agency announced the failed tests on Tuesday but said that, although Sinner will be docked 400 ranking points and $250,000 dollars, he was found to bear ‘no fault or negligence’ and is free to compete at next week’s US Open.

The 23-year-old first tested positive for banned anabolic steroid clostebol during the event in Indian Wells on March 10, then again eight days later.

Sinner was provisionally suspended, but on both occasions he successfully appealed and was allowed to continue playing while the tribunal assessed the evidence. He has, however, been docked the prizemoney and ranking points earned at Indian Wells.

World No 1 Jannik Sinner will not serve a ban after being cleared of fault following two positive anti-doping tests

The stylish Italian player has posed for Gucci photoshoots, one of many lucrative partnerships

Due to his successes on the court in the previous 12 months, Sinner has become one of the sport’s most marketable faces

And after a lengthy, behind-close-doors investigation, last Thursday at a hearing in London the player’s reason for the extremely small quantity of clostebol in his system – less than a billionth of a gram – was accepted.

The explanation provided by Sinner was that a month before travelling to Indian Wells, his fitness coach Umberto Ferrara bought an over-the-counter spray containing the steroid in Italy. Then during the Indian Wells event, Sinner’s physio Giacomo Naldi cut his finger and was advised by Ferrara to use the spray to treat the wound.

Then, according to a statement from the Sinner team: ‘The physiotherapist treated Jannik and his lack of care coupled with various open wounds on Jannik’s body caused the contamination.’

The tribunal heard that Sinner suffers from skin condition psoriasiform dermatitis, which can cause irritation and, if scratched, cuts and sores – this was accepted as the reason for the clostebol entering his body via the physio’s finger.

Sinner won the Cincinatti Open on Monday after beating Francis Tiafoe in straight sets

The tribunal also noted that: ‘There is no suggestion the tiny concentration in his system would have had any performance enhancing effect.’

Clostebol is a derivative of testosterone, and so can help muscle growth and recovery. It has been the cause of several failed doping tests in sport, especially in Italy – one of the few countries where products containing clostebol can be sold over the counter.

Sinner said in a statement: ‘I will now put this very challenging and hugely 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.’Sinner won the Australian Open earlier this year to pick up his maiden grand slam honours

Sinner won the Australian Open earlier this year to pick up his maiden grand slam honours

Jamie Singer, Sinner’s lawyer, added: ‘Anti-doping rules have to be very strict to be effective. Sadly the unfortunate consequence is that, occasionally, entirely innocent athletes get caught up in them.

‘There is no question that Jannik is innocent in this case. The ITIA did not challenge that key principle.

‘Under the rules he is responsible for his team members’ mistakes and those mistakes sadly led to the positive test.’