Tennis Star Jannik Sinner Tests Positive for Steroids—Probe Finds Unintentional Contamination

Jannik Sinner, the world’s top-ranked tennis player and a Forbes 30 Under 30 alumnus, faced a major controversy earlier this year when he tested positive for a banned steroid. However, an independent tribunal has cleared him of fault, ruling that the positive tests were due to unintentional contamination rather than deliberate use.

Sinner, 23, tested positive for clostebol, an anabolic steroid, during the BNP Paribas Open in March. The International Tennis Integrity Agency (ITIA), an independent tribunal appointed by Sports Resolution, concluded that Sinner bears “no fault or negligence” in the matter. According to the ITIA’s investigation, the contamination occurred through Sinner’s physiotherapist, Giacomo Naldi.

The ITIA’s findings reveal that clostebol, which was originally obtained by Sinner’s trainer, was used by Naldi to treat a cut on his hand. Naldi, who was not wearing gloves, inadvertently transferred the steroid to Sinner during full-body massages and bandage applications. Sinner was unaware of Naldi’s use of the drug.

Despite the tribunal's ruling, Sinner has been stripped of the $325,000 prize money and ranking points he earned at the BNP Paribas Open, where he was defeated by Carlos Alcaraz in the semifinals. The decision underscores the strict liability principle in doping cases, which holds athletes responsible for substances found in their system, even if they are unaware of their presence.

Sinner’s lawyer, Jamie Singer, stated, “Jannik is responsible for whatever is in his system, even when entirely unaware of it.” Sinner himself commented on the situation, expressing his desire to move past this “challenging and deeply unfortunate period.”

The Association of Tennis Professionals (ATP) emphasized the importance of diligence in the use of products or treatments, stating that Sinner’s case “underscores the need for players and their entourages to take utmost care.”

Sinner, who recently clinched the Cincinnati Open title, remains a strong contender for the upcoming U.S. Open, starting August 26. DraftKings gives him the second-best odds of winning the tournament, with a +200 payout for a $10 bet. Carlos Alcaraz is currently favored with +150 odds.

Jannik Sinner’s remarkable career includes becoming the first Italian to achieve the world’s top tennis ranking, winning the Australian Open, and the ATP Masters 1000 in Miami. He was also named in Forbes' European 30 Under 30 list for sports and games. Known for his endorsements with high-profile brands like Gucci and Rolex, Sinner’s rapid rise in tennis is marked by his historic achievements and recent controversies.

As the tennis world turns its attention to the U.S. Open, all eyes will be on Sinner as he continues to navigate the fallout from this incident and seeks to reaffirm his position as one of the sport’s leading figures.