Novak Djokovic reacts during his shock loss to Denis Istomin in the second round of the Australian Open

Novak Djokovic's former coach Boris Becker insists the Serb must revive his love of the game if he wants to be back on top but has not ruled out a coaching reunion.

Becker believes that since winning last year's French Open, which was Djokovic's first triumph at Roland Garros, the 29-year-old has lost his motivation.

Djokovic went from holding all four Grand Slam titles to enduring early exits at Wimbledon and the Rio Olympics and, after splitting with Becker at the end of the season, he was dumped out of the Australian Open by Denis Istomin.

Becker said: "Would I go back and coach him? I'll always be a friend and I'll always be in his corner. We are on very good terms. I don't know, let's see what happens."

Djokovic split from former coach Boris Becker at the end of last season

Becker is convinced that former charge's success at the French Open seven months ago changed his perspective.

"People don't realise what it takes to win one Grand Slam. Imagine - he won four in a row, he was the holder of the real Grand Slam," Becker added.

"A lifelong dream was fulfilled. Of course the bubble burst. Of course your mind goes off course. Of course his family wants him back. He's a human being with a big heart.

"He's a strong player and of course the motivation goes a little bit. To get it back you have to go back to the practice court and it's not easy when you've been on top."

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