Roger Federer will not have a shot to make history at the upcoming 2021 US Open in New York. On Sunday, the tennis star announced that he is withdrawing from the tournament. The 40-year-old sited a third surgery on his right knee as the reason he will be unable to compete in the tournament.

In the Instagram video, Federer expressed doubt regarding his future in general, saying he is not sure just how much this surgery will impact his career.

Here's what Federer said:

"I want to give myself a glimmer of hope also 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 right now to do another surgery and try it. But I want to be healthy and I'll go through the rehab process ... As you can imagine it's not been simple. I've been doing a lot of checks with doctors on my knee, getting all the information as I hurt myself further in the grass court season and Wimbledon."

Federer added some details of the recovery process, including that he'll "be on crutches for many weeks and out of the game for many months."

Before injuring his knee at Wimbledon earlier in the year, Federer made it to the quarterfinals of the tournament. Right now, Federer has 20 Grand Slam titles, which is tied with Novak Djokovic and Rafael Nadal for the most in men's tennis.