The Reason Behind the Dismissal of Jannik Sinner’s Fitness Coach Has Been Revealed

Jannik Sinner’s decision to part ways with his long-time fitness coach Umberto Ferrara and physiotherapist Giacomo Naldi in August 2024 was far from routine—and the reason behind it has now come into full view. While initial statements cited a “breakdown of trust,” recent reports confirm that their dismissal was directly linked to a doping controversy involving a topical spray containing clostebol, a banned anabolic steroid.

In March 2024, Sinner provided two anti-doping samples that tested positive for trace amounts of clostebol. An independent tribunal later cleared him based on evidence that the exposure had been accidental. According to Sinner’s team, Ferrara had purchased a medicinal spray in Italy and gave it to physiotherapist Naldi to treat a minor cut on his hand. Naldi then treated Sinner’s wound without wearing gloves, inadvertently transferring residue of the banned substance onto the player.

Despite being cleared by the International Tennis Integrity Agency, the World Anti-Doping Agency (WADA) appealed the ruling. After legal proceedings, Sinner accepted a negotiated three-month suspension, which ended just in time for him to participate in the 2025 Italian Open. Following this incident, Sinner made the decision to dismiss both Ferrara and Naldi from his coaching team to reestablish trust and ensure full compliance with anti-doping protocols moving forward.

Ferrara, who also has a pharmacy qualification, maintained that he had warned Naldi not to use the spray on Sinner. Nonetheless, the team viewed this lapse in judgment as a serious breach of procedure, resulting in their dismissal. Sinner’s team briefly brought in new staff, including trainers previously associated with Novak Djokovic, to stabilize his preparation.

However, after a year of reflection and having navigated the immediate fallout, Sinner recently made the decision to rehire Umberto Ferrara as his fitness coach. He cited Ferrara’s deep knowledge of his physical needs and the important role he played in his development as key reasons for his reinstatement. Naldi, however, has not been brought back.

While the move to rehire Ferrara has sparked debate among fans and commentators, many believe Sinner is prioritizing stability and familiarity as he prepares for the final stretch of the season, including the U.S. Open. The dismissal was initially necessary to handle the crisis professionally, but with lessons learned and trust rebuilt, Sinner’s team now looks to move forward with a renewed focus on performance.