Roger Federer has vowed to do 'everything he can' to get back to the top, and says he 'honestly doesn't know' when he will retire.
The Swiss star will turn 40-years-old later this year, yet his future is clouded in more mystery than ever due to requiring double knee surgery in 2020.
That has seen him play just two matches - both at the Qatar Open - in 15 months, and that makes it difficult to predict what level of tennis he is still capable of producing.
However, he has laid out his intent to prolong his career by fighting back from the injury, and he is scheduled to play Geneva later this month before a busy summer schedule that includes Roland Garros, Halle, Wimbledon, the Olympics, and the US Open.
However, if the injury does turn out to limit his attempts to return to his former glories, he has assured fans it will not be for the want of trying.
"I will do everything I can to get back to the top after my surgery and the long pause due to that," Roger Federer told Schweizer Familie.
"As long as I am happy and healthy I will continue to play.
"Now, before you even ask me for how long, I must tell you, I don't know, honestly."
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