Roger Federer has lifted the lid on his journey back from double knee surgery, saying 'there weren't many muscles left' afterwards.
Federer was forced to undergo two operations in 2020 to correct a long-standing knee problem.
He will return in Doha this week, but he says it has been a particularly tough road back, especially after the second, initially unplanned, surgery.
“I don't remember anything going wrong after the first operation," Federer told the Swiss Press. "The knee buckled, it just wouldn't [take the weight]. Something new was added.
"I did an MRI and the doctor said, sorry, I would need a second operation. There was no getting around it.
"I'm not a fan of surgeries, that is a well-known fact. The first few weeks went normally. Pierre (Paganini, his fitness trainer] wasn't involved yet, and I didn't play tennis.
"The problem was that after the second operation I went on crutches for another two weeks, as I did after the first. After that, there weren't many muscles left.
"After the first operation, I was still a top athlete, but it was terrifying to see how quickly you lose everything."
Federer will play his first match in over a year on Wednesday against either Dan Evans or Jeremy Chardy.
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