Jannik Sinner's health becomes the center of attention ahead of the US Open.

Jannik Sinner is heading into the 2025 US Open with the goal of retaining his championship, but his decision to pull out of the Cincinnati final has put a question mark over the world number one’s health.

World number one Jannik Sinner arrives at the 2025 US Open as the reigning champion and a top contender. However, his withdrawal from the Cincinnati Open final on August 18 due to illness has cast doubt on his campaign to defend his crown in New York.

Right from the start against Carlos Alcaraz, Sinner appeared sluggish. He quickly fell behind 0-5 in the first set and was forced to retire, apologizing to the Ohio crowd. According to Tennis World USA, the Italian star had been battling a high fever and flu symptoms since the previous night leading up to the match.

Sinner also admitted that the extreme heat and humidity in Cincinnati made things even tougher, calling it "one of the hottest tournaments we've ever played." He later announced his withdrawal from the mixed doubles match at the US Open on August 19.

The question now is how quickly Sinner, only 24 years old, can recover in time to compete at the final Grand Slam of the year. Alongside Alcaraz, the two have dominated tennis by capturing all seven of the most recent Grand Slam titles. Despite boasting an impressive 31 wins and just 4 losses in 2025, three of Sinner’s defeats have been at the hands of the Spanish rival, who is now surging into Flushing Meadows with a chance to claim the world number one ranking.

Prior to the August 18 final, Sinner had been in near-perfect form, not dropping a single set since winning Wimbledon—his fourth career Grand Slam trophy. “This was a very positive week for me,” Sinner said after pulling out in Cincinnati, where he was the 2024 champion. “Reaching a Masters final is always a great achievement. I still have areas to improve if I want to go deep at the US Open. This is a good opportunity to assess where my level is.”

Sinner emphasized that his focus is always on the biggest stages in tennis. “I truly love the Grand Slam tournaments. These are the most important events of the season and my career,” he shared. “The US Open will definitely be tough, but I’m excited for it. If I’m physically and mentally ready, I’ll give it everything I have.”

“Right now, a few days of rest is my top priority. After that, I’ll get back to training and hopefully be ready for the tournament,” Sinner concluded.