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Jannik Sinner Shares Update on His Future With Coach Darren Cahill

Originally posted on Athlon Sports | By Demi Phillips | Last updated Oct 21, 2025 4:47 PM ET

International tennis star Jannik Sinner showed up to the Erste Bank Open with two things on his mind. He wants to finish the indoor swing strong, and he wants his longtime coach, Darren Cahill, beside him in 2026.

Speaking in Vienna this week, Sinner referred to Cahill “like a second father” and said he plans to have a long talk after the season to keep the partnership going.

Ahead of his Vienna opener, Sinner told ATP Media he will “try to convince” Cahill to continue. He acknowledged that the Australian coach had planned to step back after 2025, but praised his influence on the team’s tough moments and day-to-day standards.

For a 24-year-old who just posted a season with two majors and four Slam finals, stability is part of his performance.

Why Cahill’s Voice Still Matters

Over the years, Cahill has guided Andre Agassi, Lleyton Hewitt and Simona Halep. Since joining Sinner alongside Simone Vagnozzi in 2022, he has been credited with sharpening serve patterns, point construction and composure between points.

There is also a relationship layer here. Sinner has been open about how much he trusts Cahill’s presence on the road. When a coach helps you rise from promising to prolific, reducing that voice can carry real cost. That is why this Vienna storyline feels bigger than a typical end-of-season check-in.

The timing is not random as well. Sinner is world No. 2, he won the Australian Open and Wimbledon this year, and he is trying to carry that form through Vienna, Paris and the ATP Finals in Turin. Keeping the right voices around him matters.

Tennis star Jannik Sinner of Italy celebrates.Susan Mullane-Imagn Images

Vienna Sets the Stage

The Erste Bank Open runs Oct. 18-26 at Wiener Stadthalle and Marx Halle. Sinner is a past champion in Vienna and is slated to start against Germany’s Daniel Altmaier. The tournament’s own coverage captured the mood on site this week, from packed practices to a busy media day.

It is a comfortable spot for Sinner geographically and emotionally. He has family in town and a history with the event. The environment fits a player trying to control details on and off the court.

Sinner’s Other Big Decision This Fall

Sinner will skip the Davis Cup Finals in Bologna from Nov. 18-23 to prioritize training for his Australian Open title defense.

He explained that even one extra week of focused work can change the start of a season. Italy’s captain confirmed his absence when naming the squad, and Sinner reiterated the reasoning in Italian media.

That choice lines up with the choice of keeping his longtime coach. If the goal is to make another push at No. 1 and the majors, Sinner has to protect his time, his legs, and in this case, his inner circle.

This article first appeared on Athlon Sports and was syndicated with permission.

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