Roger Federer says he is "feeling strong and excited for what’s to come" as he recovers from his latest knee operation at the age of 40.
The 20-time Grand Slam champion said in August he would be sidelined for "many months" because he required a third procedure on his right knee in 18 months in order to give him "a glimmer of hope" that he can return to competition.
Federer had two procedures in 2020 which resulted in more than a year of rehabilitation before a return to action in March, however, he suffered another setback during his run to the quarter-finals at Wimbledon in July.
"I'm feeling actually really good ... things are not as I hoped they would be, but I'm recovering well and the rehab is going really good," Federer told Eurosport.
"I've had no setbacks. I'm feeling strong and excited for what's to come. I wish I could be back on a tennis court as quick as possible, but I have to be patient.
"It's a slow period right now. And I got to take it step by step. And so far so good. I'm very happy."
Federer, who missed the US Open as a result of the surgery, also believes it remains possible for the Calendar Slam to be achieved after Novak Djokovic fell at the final hurdle in New York earlier this month.
World No 1 Djokovic was bidding to become the first man since Rod Laver in 1969 to win all four Grand Slams in the same year - and surpass Rafael Nadal and Federer with a record 21st major - but lost in straight sets to Daniil Medvedev.
"I think it is possible that it's going to happen again," said Federer. "We saw it with Novak, myself and Rafa that we come extremely close.
"But I think you need a bit of luck. You need perseverance, strength ... that's why I think it's going to be hard. But it's possible.
"And I have to ask also what Laver thought because he was sitting first row watching Novak play. But what Novak did this year was, of course, truly exceptional."
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