Swiss tennis star Roger Federer has announced that he will undergo another knee operation.

The 20-time Grand Slam champion has been sidelined since losing in to Poland’s Hubert Hurkacz in the Wimbledon quarter-finals and had already pulled out of the Toronto and Cincinnati Masters 1000 events.

Federer, who turned 40 on 8 August, has been plagued by knee injuries in recent times after undergoing two knee operations in 2020.

The latest knee operation means Federer will miss the upcoming US Open and almost certainly the remainder of the 2021 season.

“For me to feel better I will need surgery, so I decided to do it. I will be on crutches for many weeks and also out of the game for many months,” Federer said on his Instagram account on Sunday.

“It’s going to be difficult, but at the same time I know it’s the right thing to do because I want to be healthy… I want to be running around later [on in life] again. And I want to give myself a glimmer of hope to return to the tour in some shape or form.

“I am realistic, don’t get me wrong, I know how difficult it is at this age to now do another surgery. But I want to be healthy. I’ll go through the rehab process.”

Federer’s most likely return to the ATP Tour could be at the 2022 Australian Open.

Picture: ATP Tour – Twitter