Goran Ivanisevic has described Novak Djokovic as a 'rock' mentally, saying he especially thrives when written off.
Djokovic won his 18th Grand Slam title at the Australian Open last month, overcoming an abdominal tear and a torrent of criticism in the media to close to within two majors of Roger Federer and Rafael Nadal.
Ivanisevic was Djokovic's primary coach for the tournament, and he has paid tribute to the Serbian's sheer force of will.
"Uli (Ulises Badio, Novak’s physio) really is a miracle worker," Ivanisevic told Sasa Ozmo for Tennis Majors.
"He managed to get him ready each and every time on the table, there were painkillers involved as well and no practice, so we did warm up a bit longer than usual.
"But all of that would not be worth anything if Novak was not so strong mentally.
"I have never met such a mental rock like him, I think he is one of the mentally toughest athletes in the world, not just tennis players.
"When everyone is writing him off, he somehow finds a new source of energy; I can see how much effort he puts into that and how complicated sometimes it can be."
Djokovic's tournament looked like it could be over after he suffered the injury in the third round of the Australian Open.
However, Ivanisevic believes it was that mental strength that again got him through it.
"After the injury, I was there when the doctors told him what had happened and what the risks are if he keeps playing.
"He was told it could get worse, but he made a conscious decision saying: “I will do whatever it takes to try to win this Slam.”
"We had the same ritual every day, it revolved around his treatments and in the last two matches he was able to play with minimal pain, particularly compared to the matches with Raonic and Zverev.
"Novak is just stronger than everybody else and people have a hard time admitting that.
"His mind is so strong, he believes in his mental exercises and with those relaxation methods of his he was able to minimise the pain as much as it was physically possible, with the help of painkillers as well.
"Novak was solely focused on that title from the moment he stepped foot in Australia."
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