Roger Federer will miss US Open after announcing further knee surgery

Tennis great Roger Federer will miss the US Open later this month and possibly the rest of the season, after announcing that he needs another knee surgery which will sideline him for "many months."

"I've been doing a lot of checks with the doctors, as well, on my knee, getting all the information as I hurt myself further during the grass-court season and Wimbledon," the 40-year-old said in an Instagram post Sunday. "Unfortunately, they told me for the medium to long-term, to feel better, I will need surgery, so I decided to do it. I will be on crutches for many weeks and then also out of the game for many months."