Novak Djokovic has been described as a 'winning institution' by coach Goran Ivanisevic, who says it creates pressure for his coaching team.
Djokovic has been the most dominant player in the men's game in recent years, and last month surpassed Roger Federer for the most weeks spent at world number one.
The Grand Slam record - currently shared by Federer and Rafael Nadal with 20 apiece - is next on Djokovic's list of targets, and he closed to within two by winning the Australian Open in February.
Ivanisevic, though, says none of that happens by accident, and Djokovic's drive to constantly improve is the reason behind it.
“I just think with Novak, today is good," Ivanisevic said. "Tomorrow is not good anymore it has to be better.
"Every day has to be better every day you have to improve, you have to you know it pushes you to be better, to be a better coach and you know you just, and you see the results you know results.
“But it’s not easy. It’s a lot of ups and downs, a lot of pressure, because a final is not good enough.
"It’s like saying you’re coaching football club Real Madrid, you know, you lose two games and they encourage you to go. They want to kick you out.
“So now he is institution, he is only records, records, win win win and it’s a lot of pressure, but life without pressure is boring.”
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