Jannik Sinner’s former fitness coach, Umberto Ferrara, has finally spoken out about the doping controversy that cast a shadow over the Italian tennis star’s career. Breaking his silence since his dismissal from Sinner’s team, Ferrara offered his side of the story, adding more nuance to a saga that has captivated the tennis world for months.
Back in February, the World Anti-Doping Agency (WADA) confirmed a three-month suspension for Sinner, stemming from two failed drug tests in March 2024. However, the case took a dramatic turn in August when the International Tennis Integrity Agency (ITIA) announced that Sinner would not face a formal ban, citing “no fault or negligence” after clostebol—an anabolic steroid—was found in his system during and after the Indian Wells Masters.
An independent panel accepted Sinner’s claim that the banned substance was unintentionally absorbed. According to his explanation, it had entered his bloodstream through physical contact with his former physiotherapist Giacomo Naldi, who had applied a steroid-laced spray on a cut to his own finger. Sinner’s legal team argued this incidental contact led to the contamination.
Nonetheless, WADA remained unconvinced. In September, it took the matter to the Court of Arbitration for Sport (CAS), pushing for a one- to two-year ban on the world No. 1. But before the case could be argued in court, both parties settled—the agreement resulting in Sinner serving a retroactive ban from February 9 to May 4. By then, Sinner had already made a tough call to cut ties with both Ferrara and Naldi, pointing to their roles in the mishap.
“I want to start with [saying] that they have been a huge part of my career,” the 23-year-old said.
“We made an incredible job, bringing a lot of success and then having a great team behind me. Now, because of these mistakes, I’m not feeling that confident to continue with them. I was struggling a lot in the last months. Now I was waiting for the result, and now I just need some clean air.”
In a recent sit-down with La Gazzetta dello Sport, Ferrara shared a more personal perspective, admitting to long-term use of the medication containing clostebol but firmly denying any direct involvement in the doping episode. He pinned responsibility on Naldi for failing to observe the clear precautions he claims to have outlined.
“I have been using it for years as prescribed by a specialist as a support drug for a chronic disease,” Ferrara said. “I was perfectly aware of the ban and I have always kept it with the utmost caution, in my personal beauty case. I could have needed it for my pathology and to have it available, being abroad.
“I didn’t give anything to Naldi, I suggested using it because he had a cut on his finger that wouldn’t heal and made his job difficult.
“I was very clear in communicating to Naldi the nature of the product and the need for it not to come into contact with Jannik for any reason.
“In fact, I allowed its use only inside my personal bathroom. Naldi didn’t deny having been informed, but said he didn’t remember.”
The moment Ferrara heard about Sinner’s positive test, his reaction, he said, was one of sheer disbelief. Connecting the banned substance to the spray—Trofodermin—was, to him, an immediate realization. Acting swiftly, he and others retraced every step, gathering receipts and pharmacy documentation from Bologna to prove the origin of the product.
“Disbelief and amazement. Hearing about clostebol, the connection with Trofodermin (the medication) was immediate,” he said. “In a few hours, we reconstructed the steps that led to Jannik’s contamination and I provided evidence of the purchase of the spray at a pharmacy in Bologna.”
While Ferrara acknowledged missteps, particularly in trusting others with such sensitive matters, he also expressed frustration with how his role in the case was portrayed.
“With hindsight, it’s easy to say that I wouldn’t do the same things again. I certainly wouldn’t rely on the behaviour of others.
“I was hurt by the superficiality, sometimes aggravated by bad faith, with which many people treated my position in the affair.”
Despite being caught in the crossfire of one of tennis’ most talked-about doping cases, Ferrara held nothing but admiration for Sinner’s maturity and mental toughness throughout the ordeal. For a player still in his early twenties, Sinner’s ability to stay composed amid the chaos impressed his former coach.
“Despite his 23 years, he has shown an extraordinary maturity in dealing with the situation, in my opinion supported by the correct belief of being right,” Ferrara said.
“He has a special work ethic and dedication, this approach leads him to continually raise the bar. Working with Jannik is rewarding and stimulating.
“The last time we saw each other was in Doha and we said goodbye. I was very saddened by the end of the relationship, but I was aware that it could be one of the possible epilogues.”
Now working alongside Matteo Berrettini, Ferrara is trying to move on from a turbulent chapter. Yet, as he reflects on his time with Sinner, it’s clear the sting of how it ended still lingers. The saga serves as a cautionary tale—about the fragility of reputations, the importance of transparency, and the ripple effects of even an unintended mistake in the high-stakes world of professional tennis.