World number one Jannik Sinner has withdrawn from the Cincinnati Open due to a persistent knee injury, though he remains hopeful of featuring at the US Open.

Sinner swept the first five ATP Masters 1000 tournaments of 2026, capturing titles at Indian Wells, Miami, Monte-Carlo, Madrid and Rome.

Despite winning Wimbledon for the second time in July, Sinner then opted out of the Canadian Open, saying he needed to prioritise his long-term fitness.

Carlos Alcaraz – who has endured an injury-hit campaign and is doubtful for the US Open – also withdrew from the Montreal event, as did Novak Djokovic.

Felix Auger-Aliassime suffered an injury after the event started, while early exits for Alexander Zverev, Daniil Medvedev and Taylor Fritz left the men's draw wide open.

And it could be a similar story in Ohio, with Sinner – who won the tournament in 2024 before retiring from the 2025 final versus Alcaraz – now confirmed as an absentee. 

"After consulting with my doctors and my team, I have to announce that I need to withdraw from the Masters 1000 tournament in Cincinnati," Sinner said in a press release.

"My right knee has been bothering me, and even though we have been working hard with my medical team, I have to accept that I'm not ready to compete yet.

"I'm very disappointed not to be able to play in Cincinnati. I can't wait to be back next year, and I'm now focusing on getting ready for the US Open."

Jannik Sinner has withdrawn from the Cincinnati Open due to a right knee injury.

Wishing all the best to our 2024 champion and can’t wait to see you again next year!  pic.twitter.com/wYHY94viCE

— Cincinnati Open (@CincyTennis) August 9, 2026

The Cincinnati Open main draw begins on August 13 and runs through to August 23.

Djokovic is currently slated to compete, though Alcaraz will be absent again, with Zverev set to be the top seed. 

Sinner now has limited time to prepare for the final grand slam of the year, with the US Open main draw getting under way on August 30. 

Lifting the trophy at Flushing Meadows would make 2026 the third successive year in which Sinner has won multiple majors, after 2024 (Australian Open, US Open) and 2025 (Australian Open, Wimbledon).