The knee problem that has cost Roger Federer a year of his tennis career had been 'causing him problems for a year,' says his fitness coach.
Federer underwent surgery in February last year, shortly after he broke down with injury at the Australian Open, and then again in July.
It was assumed at the time that the surgery was related to that problem, which he sustained against Tennys Sandgren in the quarterfinals, but his long-time coach Pierre Paganini says that was not the case.
"This knee issue had been causing him problems for several years," Paganini told Tages Anzeige ahead of Federer's comeback in Doha next month.
"You could have them under control, with adapted planning and specific exercises. He and the whole team had been working on it for a long time.
"The fact that a player who has played over 1,500 matches has several maintenance points on his body is part of everyday life.
"Roger is someone who always looks at things positively, and as long as he could play and train freely, it wasn't a big problem either.
"When it became one and he decided to have an operation, he took full responsibility.
"In public it looked like everything was okay just now, then suddenly he was operated on. For us it was a process that led to this point."
Federer also had a surgery on his knee back in 2016, and he came back brilliantly from that one.
He was back within six months then, though, where as it has been over a year this time around.
"The big difference is when he paused from Australia after Wimbledon in 2016, his muscles were actually always there.
"This time we had a total interruption in which the muscles deteriorated considerably.
"There was a long time between the first operation and the moment in July when we said we could slowly start working progressively again.
"His muscles were no longer in the same condition at all, the imbalances were extreme.
"His muscles could no longer work immediately and needed a longer recovery time. When I started working with him, we were at the bottom.
"That means you try to do everything that is possible.
"At the same time, you have to do it several times so that the body learns to endure repetitions at a certain level. And then you have to pause and see how the body reacts."
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