Sinner coach reveals key change after US Open loss to Alcaraz

Jannik Sinner has been having an impressive 2026 season on the ATP Tour.

It wasn’t the best of starts for him though, after failing to defend his title at the Australian Open and getting knocked out early at the Qatar Open. Still, he’s looked like a different player since then.

Sinner went on to win both Indian Wells and Miami without losing a set, becoming the first player since Roger Federer in 2017 to complete the Sunshine Double. He also added to his streak of consecutive sets won at ATP Masters 1000 events.

A key factor behind this run has been his serve. His coach, Simone Vagnozzi, says it’s something they’ve put a lot of time into recently.

Jannik Sinner’s coach details changes made to his game

Vagnozzi works alongside Darren Cahill, and he was full of praise for his colleague during a recent interview with Sky Sports.

He added: “I really hope he stays with us for the rest of my career together because we have a really, really good chemistry together and the most important thing is that we respect each other a lot.

“And after Turin last year, he decided to stay with us, and it’s really, really important for us because to have such a great person and a great coach, it’s just helpful for us.”

“Last year after the US Open, especially in Beijing, we start to change a little bit the rhythm of his serve, the toss. And from Shanghai, he start to serve really well.

“The percentages of his first service were higher than before the season is really, really going better and better. You know there is no magical end. It’s just a lot of repetition, a lot of work.”

“For sure it’s one of the most difficult times. You know you change from almost six seven months of hard court to clay court and it’s after the first few weeks.

“We always tried to work day by day on sliding on the court try to change you know the ball you know you have to play more wide more variation some drop shots more.”

“There are a few changes that we still have to put in this game but every match that we play here is a bonus for us.”

Jannik Sinner’s recent serving form on the ATP Tour

Sinner currently holds the top serve rating on tour, sitting just ahead of Reilly Opelka at 300. He is also the only player to have a percentage over 92% when it comes to service games won.

He has posted a first serve percentage of 63.7% over the past year and has won nearly 80% of his points behind it as well.

Sinner is hitting 58.2% of points on his second serve, and he has a clear lead in service games won by quite a margin with a mark of 92.2%.

He may not be near the top in aces per match, where he sits around mid-table at 7.4 per match, but he’s tidy with just under two double faults per game on average.

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