It’s no secret, Jannik Sinner has raised the bar in the past two years. He burst onto the pro scene in 2018 at just 16, wasting no time in making his mark. His breakthrough came a year later when he stormed to his first ATP title at the Sofia Open in 2019. From there, he looked unstoppable, stacking up trophies and catapulting himself into the global spotlight. Today, he owns 20 ATP titles, four of them Grand Slams, all at just 23! But how did the young Italian improve so fast?
Darren Cahill, who’s been in Sinner’s corner since 2022, may have the answer. He and Simone Vagnozzi joined Sinner’s team within six months of each other in early 2022. Since then, the Italian has collected four Grand Slam titles, the Nitto ATP Finals crown, and four ATP Masters 1000 trophies. The bigger the stage, the more explosive Sinner becomes. He even ruled as World No. 1 for 61 straight weeks.
Speaking to ATP Media in Cincinnati, the Aussie coach laid it out plainly. Sinner has worked on one thing relentlessly since this coaching duo arrived. “One thing I did say is, ’The serve needs to improve. You’re six foot four and you’re a strong lad’. You need to be able to get more miles per hour on that first serve, better direction on that first serve. Then not only do you start winning some free points from your first serve, but also your Plus One becomes much more effective. If people can neutralise your serve, you have to work much harder for your points.’” But is that true?
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For the most part, yes. Sinner holds an excellent record against most players, especially his biggest rival, Carlos Alcaraz. But two years ago, that wasn’t the case. His first serve percentage in 2022 sat around 58%, according to ATP stats. By 2023, he’d introduced a new service motion midway through the season, lifting that number to 60%. In 2024, it nudged up again to 61%. It’s steady progress, but still a work in progress.
That showed in his latest Cincinnati clash against Gabriel Diallo on Monday. Yes, Sinner beat the Canadian in straight sets, but it wasn’t all smooth sailing. Comparing the serving stats from his two matches at the tournament so far, there’s a clear dip. His first serve percentage dropped to just 50% in the battle with Diallo.
But as Cahill says, Jannik is never satisfied. “Then his questions came, one after the other… It’s typical of him. He wants to compete. He’s a competition animal.” True to his coach’s words, the Italian was far from happy with his Diallo performance.
Jannik Sinner reveals his disappointment on his form
After cruising past Daniel Elahi Galan in his opener, Sinner admitted there were three areas he still wanted to sharpen. And after his latest win over Gabriel Diallo, the defending Cincinnati champion called it “a very difficult day at the office.” Sinner said, “He was serving very very well, especially in the second set. Against big servers you always have to find the right balance at the back of the court. Today, I struggled a bit at times. But still very happy. I need these tough matches to get used to very difficult situations.”
The third-round clash had its own drama before a ball was even struck, a 75-minute power cut delayed the start, knocking out the TV feed and electronic line calling. When play finally began, Jannik Sinner was broken in his opening service game. But the Italian flipped the script fast, snatching three straight breaks to claim the first set.
The second set was a different story, a tight, serve-dominated battle that went all the way to a tie-break. Sinner dug in and held his nerve to close it out, staying on track to defend his title. “I’m very happy this happened before a Grand Slam,” he said. “Hopefully, these situations I can keep for the main goal here in U.S.” Even so, he knew Diallo had pushed him hard. “These matches can go, at least in a third set, if you don’t play well or serve well in important moments, you can lose matches like this.”
The world No. 1 was honest about the performance. “Can I do things better? Yes. But not every day is the same. So I’m very very happy.” Next up, he faces French qualifier Adrian Mannarino. Will Sinner level up again, and take one step closer to defending his Cincinnati crown? We’d love to know your thoughts in the comments below!
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