World number one Jannik Sinner has been cleared of any wrongdoing after twice testing positive for a banned substance in March.

The Italian tested positive for low levels of a metabolite of clostebol – a steroid that can be used to build muscle mass – during Indian Wells.

A further sample taken eight days later also tested positive for low levels of the same metabolite.

A provisional suspension was automatically applied but, as Sinner challenged it successfully, he was able to keep playing.

The International Tennis Integrity Agency (ITIA) carried out an investigation which found Sinner was inadvertently contaminated with the substance by his physiotherapist.

The physiotherapist had been applying an over-the-counter spray available in Italy to a cut on his own hand.

He had then carried out treatments on Sinner, resulting in inadvertent contamination.

The ITIA accepted the explanation and that the violation was not intentional.

Sinner was cleared of fault or negligence by an independent tribunal last week.

He will, however, lose the ranking points from Indian Wells, where he was beaten in the semi-finals by eventual champion Carlos Alcaraz.

“I will now put this challenging and deeply unfortunate period behind me,” Sinner said in a statement.

“I will continue to do everything I can to ensure I continue to comply with the ITIA’s anti-doping programme.

“I have a team around me that are meticulous in their own compliance.”

Clostebol is often found in products to treat swelling and irritation. It is on the World Anti-Doping Agency’s list of prohibited substances.

Sinner was ruled to bear no fault or negligence for the positive tests.

The ITIA described the levels found in Sinner’s sample as “low”. His lawyers said it amounted to “less than a billionth of a gram”.

A statement from his lawyers said Sinner’s fitness trainer had “purchased a product, easily available over the counter in any Italian pharmacy, which he gave to Jannik’s physiotherapist to care for a cut on the physiotherapist’s finger”.

The physiotherapist applied the spray between 5-13 March, with Indian Wells taking place from 6-17 March.

During that time, the physio provided daily massages and sports therapy to Sinner, resulting in “unknowing transdermal contamination”.

“The physiotherapist treated Jannik without gloves and coupled with various skin lesions on Jannik’s body caused the inadvertent contamination,” the lawyer’s statement read.

The ITIA consulted with scientific experts, who said Sinner’s explanation was plausible, before carrying out its own investigation.

Sinner and his team fully co-operated with the investigation.

The ITIA accepted his explanation and that the violation was not intentional before referring the case to an independent tribunal to determine “what, if any, fault the player bore and therefore the appropriate outcome”.

The independent tribunal subsequently determined a finding of no fault or negligence, meaning the 23-year-old would not be suspended.

However, he will lose his 400 ranking points and $325,000 prize money from Indian Wells.