Danish rising star Holger Rune has declared he doesn't fear Nick Kyrgios ahead of the Australian Open starting on Monday.

Rune, 19, is already in the ATP world top 10 and seeded ninth at Melbourne Park.

If both men win their first two Grand Slam matches, a showdown awaits in round three.

'I have to take one match at a time – everybody is tough – but, of course, it could be fun,' Rune said.

'Nick is always playing great. When he's playing, he's on and he's super dangerous... I'll take the fight, for sure. I'm not afraid. I'm just going to go out there and play my tennis.

'It's good for the sport that we have a guy like Nick, who can cheer the crowd like he does.

'It's better to play with a full stadium that is loud than in front of nobody, so I see it as a positive.'

Like Kyrgios, Rune was a junior world No.1 and has a fiery temper.

His talent is obvious - Rune won the Paris Masters in November, beating five top players -  Carlos Alcaraz, Felix Auger Aliassime, Andrey Rublev, Hubert Hurkacz and then Novak Djokovic in the final.

He also made the quarter-finals at the French Open last year.

Kyrgios faces Russian Roman Safiullin in his first round match on Tuesday.

The 27-year-old local hope, a Wimbledon finalist last year, has declared if he wins the Australian Open - or another Grand Slam - he may retire from the sport.

The Canberra-born star admitted he struggles to commit to the 'dedication' required to perform at the highest level.

'100 per cent,' Kyrgios said after his exhibition match with Djokovic on Friday. 

'It's a lot of training, a lot of work, and I just want to be able to eat whatever I want, drink what I want to drink.

'It's a hard lifestyle. The dedication these guys show...I did a bit of that last year to show the world I'm still one of the best.

'But I'm going to try and do it this year and hopefully I can do it, but it will be hard.'