Roger Federer has withdrawn from the National Bank Open in Toronto and the Western & Southern Open in Cincinnati due to a knee injury.
The 39-year-old underwent two knee surgeries in 2020 and has only played five tournaments this year as he looks to get back to full fitness.
He most recently competed at Wimbledon, where he reached the quarter-finals, before pulling out of the Tokyo 2020 Olympics because he suffered “a setback” with his knee.
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He will now not play for at least the next two weeks due to the knee problem, putting his participation at the US Open in doubt.
The National Bank Open starts on August 7, with the Western & Southern Open on August 14 before the final Grand Slam of the year in New York on August 30.
Tokyo gold medallist Alexander Zverev will also not compete in Toronto.
He said in a statement: “I regret to inform you that, unfortunately, I have to withdraw from the National Bank Open in Toronto. Due to the intense past couple of weeks and my incredible experience at the Olympics, I need to recover so that I can hopefully be at my best for the remainder of the US summer swing.
“It was a difficult decision for me as I have had great memories from Canada and I can’t wait to be back next year!”
Matteo Berrettini, Pablo Carreno Busta and Canadian Milos Raonic have also pulled out while the women’s event in Montreal has been hit by the loss of Naomi Osaka, Sofia Kenin and Iga Swiatek.
Novak Djokovic, Rafael Nadal, Andy Murray and Serena Williams are currently set to play in Cincinnati.
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