ATP Tour

Making Sinner a winner: Why a 'united voice' is key for co-coaches Vagnozzi, Cahill

Simone Vagnozzi has been instrumental in developing one of the ATP Tour's top partnerships, doing so with little fanfare and quiet consistency.

The Italian coach, who has been working alongside Jannik Sinner since February 2022, has helped steer the 23-year-old's remarkable ascent to the top of the PIF ATP Rankings. His work behind the scenes — along with co-coach Darren Cahill — is a journey of patience, precision, and relentless preparation.

“It’s a wonderful position, something we’ve been seeking for the last three and half years,” Vagnozzi told ATPTour.com. “Getting to No. 1 means going to every tournament with the intention of winning it. As we always say in our team, the important thing is trying to work and prepare as well as possible to have the chance to compete and win titles as much as possible. The important thing for us is to have the peace of mind that we have done things as well as possible.”

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The balance between being demanding and approachable is one of the keys to their success. In a team where everything is shared, the presence of Cahill and his experience has been essential for maintaining focus.

“I have to say that I’m so lucky to have met someone like Darren, both professionally and personally,” said Vagnozzi. “We connected immediately, and that undoubtedly helped us in our journey. It’s never easy to find that chemistry, but we’ve always prioritised Jannik’s interests.

“In practice, we have different roles; I’m responsible for the more technical and tactical side of things, and he is more in charge of the mental and emotional aspects. Of course, we share everything, and the most important thing is that the player always hears one united voice.”

Cahill, who was planning to stop coaching Sinner at the end of the year to spend more time at home, made a deal with his player before the Wimbledon final that may yet change his plans; if the Italian won the title, he would be able to choose whether or not Cahill continued.

“Honestly, nothing’s certain at the moment,” admitted Vagnozzi. “But we’ll all be happy if Darren stays.”

_{^{Darren Cahill and Simone Vagnozzi cheer for Jannik Sinner during the 2025 Wimbledon final. Photo: Clive Brunskill/Getty Images.}}

Vagnozzi does not believe that the coach’s role is diminished when their player reaches the top. Quite the opposite: “We’re talking about athletes that are so demanding that they don’t want just friends, so to speak, they want people who help them to reach their maximum potential... They want honest people who sometimes tell them things they don’t want to hear.”

That journey to the top improves the player, of course, but also the coach. Vagnozzi is no exception to this rule.

“The experience undoubtedly helps, experiencing new situations and working with different athletes,” explained the Italian. “I think the best coaches are those that get excellent results with different athletes. It’s up to us to understand how to bring value to them, and that’s why we have to be like chameleons, because you can’t use the same method with different players.”

Sinner, who has won four major titles and spent 59 consecutive weeks as the world No. 1, has a seemingly bottomless reserve of ambition. It is one of the keys to his astonishing success.

“He’s a very calm person, and he’s very mature for his age. He knows exactly what he wants to achieve in life,” said Vagnozzi. “But he’s also a fun and ingenious 23-year-old kid, he’s a great guy to be around off court. His secret is precisely that; the constant desire to improve, never being satisfied. Without that, finding enough motivation to go out on court and practise would be really difficult.”

For Vagnozzi, such an attitude cannot be built on court. “It’s essential for the player to also study on their own,” said the Italian. “It’s a way of visualising the match. It’s important that we provide them with the information and analysis, and then for them to take it on.”

In that analysis, there is one name that frequently crops up: Carlos Alcaraz, clearly Sinner’s most demanding opponent.

“Carlos is such a special player that he creates problems for you that other players cannot,” Vagnozzi said of Alcaraz, who leads Sinner 8-5 in their gripping Lexus ATP Head2Head series. “Therefore, it’s essential to prepare as well as possible to resolve the conundrums he sets you. The more you practise those situations in practice, the more comfortable you’ll feel in the match.”

That constant evolution and emotional management plays a fundamental role.

“As with everything, I think equilibrium is the real quality a player must have,” said Vagnozzi. “Keeping your feet on the ground when things aren’t going well and not getting down on yourself when things don’t go as you expect.”

With his feet firmly planted on terra firma, but his eyes always on the prize, Vagnozzi has been with Sinner every step of the way, and he is not ready to stop just yet.