Roger Federer pulled out of the upcoming hard-court tournaments in Toronto and Cincinnati on Thursday, citing lingering issues with his surgically repaired knee and shedding doubt on his status for the U.S. Open.
The withdrawals by Federer, who turns 40 on Sunday, were announced separately by the two events.
This news follows the 20-time Grand Slam champion's decision to sit out the Tokyo Olympics after he said he “experienced a setback” with his knee during the grass-court season.
Federer has not competed since losing in the Wimbledon quarterfinals to Hubert Hurkacz on July 8.
Play begins at Toronto on Monday, and at Cincinnati on Aug. 16. They traditionally are the two primary tuneups ahead of the U.S. Open, the year's last Grand Slam tournament and scheduled to begin Aug. 30 in New York.
Federer is a seven-time champion in Cincinnati and has won two titles in Canada.
Other players whose withdrawals from Toronto were announced Thursday: Olympic gold medalist Alexander Zverev, Wimbledon runner-up Matteo Berrettini, Milos Raonic and Pablo Carreño Busta. Novak Djokovic pulled out last month.
Federer had two operations on his right knee in 2020 and went more than a full year between matches. He returned to Grand Slam action at the French Open in late May and then pulled out of that tournament after three victories, saying he wanted to be rested and ready for the grass circuit — especially Wimbledon.
Before action at the All England club began in late June, Federer was asked about the Olympics and said he would need to wait until after Wimbledon ended to figure out his schedule.
“In previous years, it was definitely easier. At the moment, things are not as simple as in the past," he said at the time. "With age, you have to be more selective. You can’t play it all.”
When he later posted on social media that he would miss the Summer Games, Federer wrote: “I have already begun rehabilitation in the hopes of returning to the tour later this summer."
Federer, Djokovic and Rafael Nadal are tied for the men's record with 20 Slam trophies.
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