TENNIS: The coach who guided Novak Djokovic as a junior says the former world No.1's drive and dedication to the game have taken a toll on the Serb's career.
Niki Pilic, who taught Djokovic as a junior at his Munich academy, said he did not know if the 29-year-old could get his spark back.
"The hard work of the last five or six years has taken its toll," the 77-year-old Pilic said.
"Tennis was the priority every morning and afternoon and evening.
"That tenacity is no longer the same. It remains to be seen whether he can rediscover it and get back to the top level.
"All I can tell him is to be the person he was."
Djokovic looked untouchable after capturing his 12th grand slam title at Roland Garros last June.
"But loss of form and missing tournaments made his advantage melt away," Pilic said.
Djokovic lost his top ranking last November to Andy Murray and Australian Nick Kyrgios beat him in the quarter-finals of an ATP event in Acapulco last week.
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