Roger Federer is returning to tennis because his passion is still as strong as ever, says Pierre Paganini, although he admits there was discussion about retirement.
Federer will return to the court next month after 13 months on the sidelines battling a knee injury that has required two operations to correct.
It is some commitment for a player who will be 40 by the time this season finishes, but Paganini, who is the Swiss star's fitness coach, says that should tell you everything about whether or not Federer still has his love for tennis.
Asked whether Federer discussed retirement with his team, Paganini told Tages Anzeiger: "I can't imagine the player not asking such questions at all
"But when he decided to have the operation, it was logical that he did not want to think about the end of his career.
"He had chosen a route that would take several months and aim at comeback - not unpacking the suitcase."
Once that option was rejected, though, Paganini says it has been Federer's passion and love for tennis that has driven his comeback.
"[He] clearly [still has a passion for tennis]," Paganini added. "He depends on it, and so do we on his team. Otherwise he would no longer get involved in the training courses that we propose to him.
"When a player at almost 40 has to do exercises again that a 70-year-old can manage without problems, and is happy that Tuesday was better than Monday - is that not a passion!
"You have to be a positive thinking person and find the right mix between strategy and spontaneity.
"Sure, when I say something like that, people think: 'Of course, he's part of Federer's team, and Federer is also a nice guy.
"But I can't help it that it's the truth. And that I am constantly surprised myself and sometimes ask myself: Why is he still doing all this?"
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