Darren Cahill, the seasoned Australian coach, has been instrumental in Jannik Sinner’s meteoric rise in the ATP rankings since he joined the young Italian’s team in July 2022. However, the 2025 season will mark the end of their successful partnership, as Cahill has announced that he will retire from coaching after this year.
Over the years, Cahill has been a key figure behind the success of several world-class players, including Lleyton Hewitt, Andre Agassi, Andy Murray, Simona Halep, and Fernando Verdasco, with a remarkable track record of coaching four world No. 1s and four Grand Slam champions. Cahill’s journey in tennis began as a professional player, and his understanding of the game has shaped his coaching philosophy. He reached a career-high ranking of No. 22 in singles and No. 10 in doubles, alongside a semi-final appearance at the 1988 US Open.
Cahill’s influence on Sinner has been significant, and in 2024, the Italian achieved a remarkable feat by becoming the youngest player to reach consecutive singles finals at the Australian Open since Pete Sampras in 1994-1995. Cahill’s impact has also helped Sinner win 20 or more consecutive hard court Grand Slam matches, making him the second-youngest player to achieve that milestone.
As Sinner gears up for his 2025 Australian Open final against Alexander Zverev, Cahill downplayed his role in the Italian’s success, as is typical of his humble nature. “Honestly, I don’t want to make this in any way about me. We’re concentrating on Jannik making the final, playing Zverev. This is not about me. This is about Jannik,” Cahill remarked.
Reflecting on the typical length of a coach-player relationship, Cahill emphasized the importance of knowing when to step away. “A coach is truly effective for a period of three, four or at most five years. The work that Simone Vagnozzi is carrying out is of incredible quality. Sinner is in very good hands and the successes will continue to arrive,” he added.
As Cahill prepares to depart, the question of who will fill the gap remains. Several high-profile names have been linked with taking over from the Australian, and Cahill mentioned one notable conversation with Andre Agassi. “We spoke to Andre (Agassi) today – he’s a big fan of Jannik’s, loves the way he plays,” Cahill revealed. The legendary Agassi, who won eight Grand Slam titles, has offered invaluable insights into Sinner’s game, noting both areas of improvement and strengths. Cahill continued, “No two players are the same, no two players see a tennis match the same way,” highlighting the unique qualities both Agassi and Sinner bring to the court.
Despite the challenges, 2024 was a turbulent year for the Sinner camp. The Italian faced a doping scandal after testing positive for clostebol, an anabolic steroid, earlier in the year. The news was kept private, and Sinner’s team appealed the ITIA’s decision to the Court of Arbitration for Sport (CAS). In August, the appeal was successful, but the World Anti-Doping Agency (WADA) subsequently appealed the ruling. The final decision will be made in April 2025, keeping the team on edge.
Throughout this ordeal, Cahill praised Sinner’s resilience in the face of adversity. “It’s not easy to come back and defend a major for the first time in your career and he’s had some stuff to deal with,” Cahill said. “We couldn’t be prouder of the way that he’s conducted himself, both on and off the court, the fight he’s shown, the resilience.” Cahill expressed admiration for how Sinner has handled the pressure and mental strain. “Nobody’s bulletproof,” he acknowledged. “But he finds playing tennis matches to be his safe place. That’s where he can go and do his thing and feel like this is what he knows. He’s an amazing young man who’s been able to put that to one side.”
As Sinner faces Zverev in the 2025 Australian Open final, it will be the first men’s singles final between the top two seeds since the 2019 showdown between Novak Djokovic and Rafael Nadal. Despite the ongoing challenges, Cahill believes that no matter what happens, Sinner can hold his head high, proud of everything he has achieved so far. “What will be will be. We don’t know what’s going to happen, but he can always hold his head up high and be proud of what he’s been able to achieve.”
As Cahill prepares for his final year as a coach, his legacy in tennis remains undeniable, and his influence on Sinner will continue to shape the young Italian’s career for years to come.