This year alone should prove just how great Jannik Sinner is. The Nitto ATP Finals repeat champion finished the 2025 season off on a high note — the very same high note he finished last season off by winning the finals tournament. That high note, however, isn't exactly what Sinner experienced at the beginning of the year, though.
Of course, Sinner did win the year's inaugural Grand Slam in Australia, but what happened after that put Sinner's year in limbo. Sinner faced a three-month suspension, and he served it. Upon returning to the court, it was fair to question how good he would be after having missed so much time. Well, he barely missed a beat.
It wasn't the smoothest remainder of the '25 season after the suspension, as Sinner had some bumps along the way. Though those bumps were really a bump: Carlos Alcaraz. Sinner dropped several vital matches to the Spaniard throughout the year, but Sinner got the best of his rival in the end, and as it's the perfect way to close the season, it always paves the way into the next, where Sinner still has more work to do.
Jannik Sinner's coach wants to target the clay surface next year as a main area of improvement
Sinner's tennis game translates fairly well to all surfaces: hard, grass, and clay. He's won titles on all three, which only emphasizes how few his weaknesses truly are. That being said, every tennis player, no matter where they rank or how great they are, has a better court surface and a lesser one.
Rafael Nadal, for instance, is still considered the greatest clay court surface player of all time, and likely will always be considered that — his 14 French Open titles and 63 of his 92 career singles titles on clay speak to that. Nadal won on all surfaces, but hard courts were always considered his third-best surface (he once stated that grass was his second-best).
Even the great Spaniard would admit he could have done better on the hard court, and this is similar to Sinner's clay experience. It's also the feeling Sinner's coach, Darren Cahill, expressed after his star captured the title in Turin, Italy, this past weekend. Cahill was talking about the variations across the different surfaces, with the clay surface a particular focus for Sinner next year.
“As far as Jannik’s game is concerned, I think his game transitions well to all surfaces, whether it’s slow, fast or medium," Cahill said. "Obviously, clay is going to be a big target for us next year, to try to keep improving his clay court game. We’ll keep working on that. But he’s excited about playing on all surfaces, not just indoors.”
Cahill, who was expected not to return to Sinner's box in 2026, has since changed his course and will now be returning to coach the multi-Grand Slam winner, as long as Sinner wants Cahill back. Considering that Alcaraz will continue to be Sinner's number one rival in the future, it only makes sense for Sinner to do everything he can to improve his clay game, given that clay is Alcaraz's best.
Alcaraz has won two French Opens and eight other clay-court event titles, including four Masters 1000 events: 2025 Monte-Carlo, 2022, 2023 Madrid, and 2025 Rome. Sinner has just one clay court title in Croatia in 2022. All of his other titles have been won on the hard and grass surfaces.
Alcaraz is the current King of Clay, and to take the King down, Sinner must meet him at his level. Cahill, now that he's staying on with Sinner, has the opportunity to get the most out of him in 2026, and mastering clay will be high on the list of priorities.