Djokovic: Kyrgios can be one of the best if he's more professional

Nick Kyrgios is "slowly getting all the pieces together", says Novak Djokovic. Scott Barbour/Getty Images

Novak Djokovic believes Nick Kyrgios must improve his professionalism if he is to harness his burgeoning potential.

The 20-year-old Australian Kyrgios has attracted controversy with several on-court outbursts in his fledgling career, most notoriously a derogatory slur made towards Stan Wawrinka last August.

"Undoubtedly he has a great potential to be one of the world's best tennis players and I'm sure that he also has the intention and the ambition to achieve great heights in this sport," Djokovic told The Guardian Australia.

"He still needs that routine and needs a certain level of professionalism and I would say, a kind of a sacrifice, you know, for something that [he wants] to achieve. It's all about give and take in life.

"It's important as well to keep the right balance. I don't think it's really healthy to just be living and breathing and dreaming tennis but also it's not good to be on the other extreme of not really caring too much and just going along and seeing how things turn out.

"It's important to find that optimal zone where you feel comfortable and you find that necessary balance in the middle where you know what works for you the best."

But world No.1 Djokovic feels Kyrgios, who helped Australia lift its first Hopman Cup title in 17 years last week, can bring together all the different aspects required to be a top player, from the mental to the physical.

"He's got the talent, he's got the potential and he's got the strength and he's got all the arsenal of shots he needs and he's slowly getting all the pieces together."

Kyrgios reached a career-high ranking of No.25 in June, shortly before on-court microphones picked up his remarks at the Rogers Cup linking his fellow Australian and good friend Thanasi Kokkinakis to Wawrinka's girlfriend -- believed to be Croatian tennis player Donna Vekic.

He was given a suspended 28-day ban and $25,000 (£17,370) fine for the incident, and also attracted criticism at Wimbledon last summer when he appeared to throw a game in a sulk during his defeat to Richard Gasquet, having been broken in the second set.

The Australian also received a code violation for swearing in what was one of several ill-tempered displays at the All England Club, where he had an ugly exchange with the umpire in his second-round win.

"I think it's important to respect the sport," Djokovic, who cruised to the Qatar Open title last week, added. "Always try to respect your opponents ... and leave this sport with dignity and understand that you are part of something that is greater than you. Tennis is greater than all of us."

Kyrgios was forced to retire from his exhibition match at the Kooyong Classic against David Goffin with a foot injury on Wednesday, but tweeted that he will be fine to participate in the Australian Open, which gets underway on Monday.