World No. 1 Jannik Sinner to Miss Rest of Year Due to Knee Injury

Jannik Sinner of Italy plays a backhand against Rafael Jodar of Spain during the Men’s Singles Quarter Final match on Day 10 of the Mutua Madrid Open at La Caja Magica in Madrid, Spain, on April 29, 2026. Clive Brunskill/Getty Images

World No. 1 tennis player Jannik Sinner said on Oct. 6 that he needs to undergo treatment for a right knee injury that will force him to miss the rest of the 2026 season.

“Me, together with the doctors, have decided that I need a course of treatment for my knee, which means that the 2026 season is officially over,” he said in a post made to multiple social media accounts. “I will do everything possible to get back a hundred percent.”

Sinner, who said he needs to focus on his long-term health, loses the opportunity to play at the Shanghai Masters and to defend his titles at the Paris Masters and the ATP Finals. The ATP Finals are held in Turin, near where the Italian grew up.

The 25-year-old hasn’t played since the Wimbledon final three months ago, where he beat Germany’s Alexander Zverev in four sets.

After defending his title at the All England Club, Sinner pulled out of the Montreal Open as the issues with his knee began.

“After carefully considering all the factors together with my team, we have made the difficult decision to withdraw from Montreal,” he said in a statement to organizers.

Sinner went on to miss Cincinnati and the U.S. Open as concerns about his knee grew.

Carlos Alcaraz, Sinner’s main rival, has also missed a large chunk of the season due to injury—a right-wrist injury that sidelined him for four months—but made his return at the U.S. Open.

Injuries to Sinner and Alcaraz this year have opened the door for Zverev, who captured the first Grand Slams of his career this summer at Roland Garros and the U.S. Open and is all but assured to finish as the year-end No. 1 for the first time.

Despite still trailing Sinner in the live rankings, since the start of the year, Zverev is more than 800 points ahead of Sinner and more than 4,000 points ahead of everyone else.

Sinner’s Early 2026 Dominance

Sinner was on a historic run earlier this year, winning a record six consecutive Masters 1000 tournaments dating back to last year’s Paris Masters.

After coming into Roland Garros as a favorite with Alcaraz out, Sinner suffered a shocking second-round defeat against the unseeded Juan Manuel Cerundolo.

Just one game away from victory in the third set, Sinner struggled with the Paris heat and fatigue, and lost 18 of the last 20 games to lose in five sets.

He will still finish the year with an impressive 44–3 record—a 93.6 percent win rate—and six titles.