Roger Federer pulls out of two tournaments, U.S. Open status in doubt?

Tennis living legend Roger Federer hasn't competed since he crashed out of Wimbledon via a straight-set loss to Hubert Hurkacz in the quarterfinal round, as he pulled out of the Summer Olympics in Tokyo due to a setback involving his surgically repaired knee. 

Per the ATP Tour, Federer has now withdrawn from this month's National Bank Open in Toronto and the Western & Southern Open in Cincinnati because of lingering knee problems. 

Federer underwent two surgeries on his right knee in 2020 and was out for over 400 days before he returned to tournament play in March. After his loss at Wimbledon in July, he suggested he may never again play at the All England Lawn Tennis and Croquet Club, and there are now concerns about his ability to recover in time to participate in the U.S. Open held in New York City from Aug. 30 through Sept. 12. 

Missing that tournament could prove to be a brutal blow for Federer, as he, Novak Djokovic and Rafael Nadal are all tied for the men's all-time record with 20 career Grand Slam trophies heading into the year's final major competition.

Djokovic is going for the "Calendar Slam" after winning the Australian Open, French Open, and Wimbledon titles earlier this year.