Novak Djokovic says while being in top physical condition is critical for elite players, the mental side of the game is perhaps more important to becoming a Grand Slam champion.
“There are many, many players who are fit and strong, they can endure a lot on the court,” Djokovic said. “But that mental edge, that's something that you can't get it in the gym. You have to be able to play and understand who you are, get really deep into your character. Of course, you need to use the necessary experience on the court. Fail, fail, fail, but keep on coming back stronger. Eventually, that's what's going to help you succeed.”