Jannik Sinner speaks in a soft monotone, whether in his native Italian or his thoughtful, halting English. 

A clenched fist by his belly is about all the emotion he lets anyone see on the court. 

Nobody would describe anything about him as flashy; not his tennis game, not his wardrobe — which includes a lot of sweatpants and T-shirts — and not his quiet life off the court. He has freckles and a mop of wavy red hair.

Before we go much further, it’s probably healthy to add a disclaimer. We know this story is going to rely on some cultural stereotypes and generalizations about large populations in some of the biggest countries in Europe, or at least large populations of tennis players from those countries. We know there are exceptions. Many of them.

In this case, they are useful nevertheless because there is a well-earned stereotype of an Italian tennis player. They have a kind of flair lacing through their personalities and their games, whether it’s Matteo Berrettini’s booming serve or Lorenzo Musetti’s flashy backhand or the way Fabio Fognini zipped and zagged and mouthed around the court, never leaving any mystery about what he was thinking or feeling at any given moment.

If you understand Italian, you get an earful of colorful language from watching them play. When you watched these men or, in the past, Flavia Pennetta or Francesca Schiavone, there wasn’t any doubt you were watching a tennis player from Italy. 

Sinner, the 22-year-old former junior skiing champion who beat the 10-time Australian Open champion Novak Djokovic in four sets on Friday, is not that. At least not on the outside.

There’s a fairly good reason for this, according to those who know him and Italy best. Sinner comes from the small town of San Candido in the northeast corner of Italy, a region tucked next to, and with plenty of cultural commonality with, Austria and the slightly further afield Germany.  

“It’s a different part of Italy,” said Simone Vagnozzi, Sinner’s main coach during the past year. Italians from that region, Vagnozzi said, are very serious. “They don’t speak so much.”

Don’t get Vagnozzi wrong. In a quiet setting — around the hotel, or playing cards or golf (the other game that his other tennis guru, the veteran coach and commentator Darren Cahill, is trying to teach him) — Sinner is quick with a joke. 

“So it’s really serious on the court when he practices, and this is maybe the German part of him. But he is also really funny, and this is more the Italian part,” Vagnozzi said. 

This was just after Sinner crashed his coaches’ post-match news conference Friday, demanding that he be given a chance to ask the question of what it was really like to coach Jannik Sinner.

“It’s a crappy job,” Cahill answered. “We are not paid enough. The guy gives us a hard time all the time, and he’s forever actually taking our money in card games, and he gets a lot of enjoyment about that stuff.”

“Finally, the truth comes out,” Sinner said, then turned and left the room. 

Jannik Sinner, breakout tennis star and understated Gucci model (Vittorio Zunino Celotto/Getty Images for Gucci)

Sinner can often come across like a contradiction. His father is a chef and his mother waited tables in the restaurant where her husband cooked, providing Jannik with a comfortable but humble upbringing. He is a Gucci model and a Rolex ambassador. But catch him on a late summer afternoon after a morning of training at a mansion in the Hamptons during his preparations for the U.S. Open and he’s in sweats and a T-shirt and big, black-rimmed glasses, a bit amazed by, and shaking his head at, his surroundings. 

Most people don’t see those parts of Sinner — the joker or the simple young man who will always think of himself as the son of hard-working restaurant staff.

They see the face on the fascia billboards and the silent thinker who watched the two other top players of his generation, Carlos Alcaraz and Holger Rune, burst past him in 2022, even though Sinner had made the quarterfinals of the French Open as a 19-year-old, which got him labelled as a ‘next big thing’.

Sinner, aged 19, lost to Rafael Nadal in the 2020 French Open quarterfinals (Clive Brunskill/Getty Images)

Sinner preached patience. The coach who had raised him, Riccardo Piatti, the 65-year-old tennis sage known as one of the top minds in the game, had always told him to treat his first 150 tour matches as a learning experience. 

To the outside world, Sinner talked in that passive monotone about the process of evolving into a top tennis player. Inside, in the quiet settings, he was thinking something else, and it was no joking matter. 

One day, early in 2022, Sinner fired Piatti and his entire coaching team, replacing them with Vagnozzi, a new fitness trainer and physiotherapist, before this year, adding Cahill for his experience working with top players, including Simona Halep and Lleyton Hewitt.

All of them, most of all Sinner, have set themselves the task of turning Sinner into a more versatile player, someone who could do more than smack the ball from the baseline like a bot on a tennis video game. It was a two-step-forward-one-step-back approach to his career. His ranking slipped to 15 at the end of 2023 and from 10 at the end of 2022. 

Still, he talked about patience and process. Inside, it was killing him. He saw Alcaraz winning Grand Slam titles and Rune leapfrogging him in the rankings as he tried to add weight, endurance and variety to his game. Would the work ever pay off?

“Patience can be your biggest enemy in one way, because if you’re not that patient, you rush in one way, and then you forget maybe some steps that you should do to become a better player, to become better physically,” Sinner said on Friday evening. “Then at some point, I don’t know, I feel like on the level what we are seeing now from my side is because of a whole year of work, and the process of what we have made to become the best version of what I am right now.”

“Patience is not easy to handle,” he added, “It’s also practice.”

This is where Cahill has been most helpful, as a calming influence, Sinner said, someone who can keep the balance between the quiet Germanic exterior and the playful and passionate Italian interior.  The son of an Australian rules football coach, Cahill has learned the right moments to say the right words to Sinner. 

Coach Darren Cahill and Sinner at last year’s Wimbledon (Clive Brunskill/Getty Images)

They talked little about tennis for hours before Friday’s match against Djokovic. “Then 20 minutes before the match, we talked about tactics, how to handle certain situations,” Sinner said. “Cahill helped not only me but the whole team to believe in ourselves, but also to enjoy, because we travel so much around the world, and to enjoy the time together is really important.”

On Sunday, he will face Daniil Medvedev in his first Grand Slam final.

The hard work has paid off.

(Top photo: Nicolo Campo/LightRocket via Getty Images)