Two of tennis’ top stars won’t participate in the 2021 U.S. Open. Just days after Roger Federer announced that knee surgery would keep him away from the court for an extended period of time, Rafael Nadal says he’s done for the year.

A left foot injury will prevent Nadal from competing for the remainder of the 2021 tennis season. The ailment forced him to withdraw from Wimbledon and skip the Tokyo Olympics.

"Honestly, I have been suffering much more than I should with my foot for a year and I need to take some time ... to find a solution to this problem or at least improve it in order to continue to have options for the next few years," Nadal said in Spanish on Twitter Friday.

"I'm with the maximum enthusiasm and predisposition to do whatever it takes to recover the best possible shape to keep competing for the things that really motivate me.

"I'm convinced that with the recovery of the foot and obviously a very important daily effort ... this can be achieved. I will work as hard as I can to make it happen."

Nadal is the No. 4 ranked player in the world. The 35-year-old saw his streak of four straight French Open championships come to an end when he was defeated by world No. 1 Novak Djokovic in the semifinals. Nadal won his fourth U.S. Open in 2019, the last time the tournament hosted fans.

Nadal, Federer, and Djokovic are in a three-way tie for the most Grand Slams ever with 20 career championships apiece. The injuries to Nadal and Federer could clear the way for Djokovic to set a new record while winning all four Grand Slam events in the same calendar year.

Spain's Rafael Nadal withdrew from the ATP Toronto Masters before his second-round opener with a nagging left foot injury
Spain's Rafael Nadal withdrew from the ATP Toronto Masters before his second-round opener with a nagging left foot injury. GETTY IMAGES NORTH AMERICA / Mitchell Layton