Jannik Sinner couldn’t have scripted a better start to 2026, winning the Sunshine Double, completing the prestigious Career Golden Masters, and defending his Wimbledon crown. It looked like another year of Sinner dominance was well underway. But then, the plot took an unexpected turn. The World No. 1 has now pulled out of back-to-back Masters events ahead of the US Open, putting his fitness under the spotlight.

When Sinner first pulled out of the National Bank Open, the reason behind his decision remained unclear. But after he was spotted visiting an orthopedic clinic in Milan last week, injury concerns quickly began to swirl. Now, the World No. 1 has put those speculations to rest, confirming that he is dealing with an issue in his right knee, and withdrawing from the Cincinnati Masters as a result.

“After consulting with my doctors and my team, I have to announce that I must withdraw from the Cincinnati Masters 1000,” he said in a statement. “My right knee has been giving me trouble, and although we’ve been working hard with my medical team, I have to accept that I’m still not ready to compete.” Though the knee problem is a main culprit, Sinner’s issue appears to have crept up gradually rather than arriving out of nowhere.

Notably, knee pain is common in tennis and can build gradually under repeated stress. Sinner’s workload only adds to the concern, with the Italian competing regularly since January and spending months covering the court through long rallies and intense movement.

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For a player of his height, Sinner’s speed, sliding, and balance are exceptional, but that constant movement can come at a cost. After seven demanding months, the World No. 1 is now stepping away from Cincinnati to give his knee a much-needed breather before the US Open. If anything, this withdrawal probably stings a little more because of everything that happened in Cincinnati last year.

Sinner had reached the 2025 Cincinnati final and was hoping to defend his title against Carlos Alcaraz. But the match quickly turned into a nightmare. After falling two breaks behind, the Italian sat at the first changeover with ice on his head before calling for the trainer after losing another two games. Fighting back tears, Sinner eventually apologized to the umpire and officials and admitted that he couldn’t continue.

A severe viral infection, accompanied by a high fever and flu-like symptoms, had left him in no condition to carry on. After falling 5-0 behind, Sinner was forced to retire from the final, embracing Alcaraz before walking to the center of the court and raising his hands in apology to the crowd. However, Sinner has happy memories too at the Lindner Family Tennis Center.

He won the Cincinnati title in 2024 by beating Frances Tiafoe in the final and was expected to return with another strong run this year. Now, though, his withdrawal has shifted the focus to the bigger question: will he be fit for the US Open? Because there have been warning signs before.

At the French Open this year, Sinner led Juan Manuel Cerundolo by two sets before his body appeared to let him down, allowing the match to slip away. He then skipped the grass-court tune-ups before Wimbledon, a move that worked as he successfully defended his title. But less than a month later, fitness questions have surfaced once again.

Moreover, Sinner’s Cincinnati withdrawal will also come at a significant cost in the rankings, with a massive chunk of points set to disappear. He will drop 650 points, as he had reached the final last year. But this loss won’t have any effect on his position at the top. The 24-year-old currently has a 5,290-point lead over World No. 2 Carlos Alcaraz. So, it is highly likely that Sinner will maintain the spot for the coming months.

Speaking of Alcaraz, Sinner is not the only major name missing Cincinnati. While his withdrawal is a big blow to the tournament, several headline players have already pulled out from both the ATP and WTA sides.

Carlos Alcaraz, Jasmine Paolini and more have already withdrawn from the Cincinnati Masters

The defending champion, Carlos Alcaraz, also won’t be present at the event this year. He has still not recovered fully from the wrist injury that he sustained in April. The Spaniard was expected to make his much-awaited return in Cincinnati, but he will remain on the sidelines. There are also serious doubts over his participation in the US Open.

Alexander Bublik is another headline player who has pulled out of the Cincinnati Masters. But his withdrawal doesn’t come as much of a surprise, as he hasn’t played in the tournament since 2021. This is because his son’s birthday falls during the event, and he prefers celebrating it with him in person.

Holger Rune has also pulled out of the Cincinnati Masters. The Dane has been out of action since October of 2025 due to an Achilles injury. Though he is expected to be in the final stages of his recovery, it will still take time for him to regain full fitness.

Jasmine Paolini is the most notable player to withdraw from the WTA side. She is still recovering from a lingering foot injury and has taken this decision so that she can regain full fitness by the time the US Open rolls in. Having reached the final in Cincinnati last year, Paolini will definitely be gutted to miss out this year.

Victoria Mboko will also not be present at the Cincinnati Masters. She is yet to recover from the knee injury that she had picked up at the HSBC Championships. This same injury had resulted in her withdrawing from Wimbledon and her home event in Toronto. It won’t be wrong to say that the chances of her playing at the US Open are looking quite bleak.

Finally, Emma Raducanu will not be playing in Cincinnati either. She is still recovering from her stress fracture in the right lower leg. This is the same setback that had led to her withdrawal from Wimbledon. She has yet to make a competitive appearance since the HSBC Championships that were held in June.

For Sinner, Cincinnati is no longer the main concern. The real test is whether his right knee recovers in time for the US Open, where he will arrive short on hard-court match play and under fresh fitness scrutiny.