Sinner withdraws from the Paris Olympics due to tonsillitis
Sinner has not played since his quarter-final defeat against Daniil Medvedev, during which he left the court after saying he felt unwell.
The Italian wrote an emotional post on social media confirming his withdrawal from what would have been the 22-year-old's first appearance at the Olympics.
It read: "I am saddened to inform you that unfortunately I will not be able to participate in the Paris Olympic Games.
"After a good week of clay training I started to feel unwell. I spent a couple of days resting and during a visit the doctor found tonsillitis and strongly advised me against playing.
"Missing the Games is a huge disappointment as it was one of my main goals for this season. I couldn't wait to have the honor of representing my country in this very important event.
"Good luck to all the Italian athletes who I will support from home. Forza Italia."
The Italian has enjoyed a fantastic start to the 2024 season, winning his first major title at the Australian Open before being named the new world number one in June.
With Sinner out of the draw, beaten Wimbledon finalist Novak Djokovic is the highest ranked men's player competing in the Olympics, hoping to add to his 2008 bronze medal.
It is the first time that the ATP world number one will not take in the Olympics since Pete Sampras in Sydney 24 years ago.