Roger Federer's third knee surgery casts shadow over future

Roger Federer has opted to go in for a third knee surgery, putting his future in tennis in doubt.

Roger Federer had knee surgery twice in 2020 which resulted in more than a year of rehabilitation before a return to action in March, some 13 months after his Australian Open semifinal exit last year. He is set to head in for a third one this year, putting his future in doubt.