Novak Djokovic says he knows the younger players are coming to 'lead the future' of tennis, but he has warned them he won't just give it to them.
Djokovic, along with rivals Rafael Nadal and Roger Federer, have completely dominated men's tennis for 15 years.
They have won an incredible 57 Grand Slam titles between then, with Djokovic claiming 17 of them and Federer and Nadal holding 20 each.
During their time on top, only Andy Murray was able to consistently compete with them, with the British star able to wrestle the world number one spot from them a few years ago for the best part of a year.
However, players such as Daniil Medvedev and Stefanos Tsitsipas - one of whom Djokovic will meet in the final of the Australian Open - are coming on strong now, as is Alexander Zverev.
If they want a spot at the top table, though, Djokovic has told them he is going to make sure they earn it.
"Certainly they will be the leaders of the future of tennis, without a doubt, but I'm not going to stand here and hand it over to them," Djokovic told Eurosport.
"I'm going to make them work their a-- off for it.
"With all my respect about the other guys, they still have a lot of work to do."
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