Novak Djokovic and Roger Federer have dominated men's tennis at the Australian Open in recent years but a new generation of players have the skill if not the experience to knock the big guns off their perch at Melbourne Park.
Below we take a look at six of the up-and-comers who could upset the top names at the year's first Grand Slam:
ALEXANDER ZVEREV
Age: 21
Nationality: German
World ranking: 4
Titles: 10
Best Grand Slam performance: Quarter-finals of the 2018 French Open
Best performance at Melbourne Park: Third round, 2018
Zverev is now firmly ensconced in the top five in the world after winning the ATP Finals title in London in November and is considered the best bet to emerge as a new champion at the Australian Open.
The towering, shaggy-haired talent has to prove that he has the temperament to go with his game on the biggest stages, having only reached one grand slam quarter-final in 14 attempts.
KAREN KHACHANOV
Age: 22
Nationality: Russian
World ranking: 11
Titles: 4
Best Grand Slam performance: Fourth round at French Open and Wimbledon
Best performance at Melbourne Park: Second round, 2017 and 2018
Khachanov is coming off a breakthrough season when he won three titles, including his defeat of Djokovic to grab the Paris Masters crown.
The tall Russian, who is just outside the top 10 in the rankings, has a thundering serve, hits precise volleys while his heavy forehand could well be the prescription to success at Melbourne Park.
DANIIL MEDVEDEV
Age: 22
Nationality: Russian
World ranking: 16
Titles: 3
Best Grand Slam performance: Third round at the 2018 Wimbledon and U.S. Open
Best performance at Melbourne Park: Second round, 2018
Another Russian on the rise, Medvedev won three titles in 2018 and showed his form is ripe when he took down triple grand slam winner Andy Murray at the Brisbane International in the leadup to the Australian Open.
Ranked 16th in the world, he went down in the final to Kei Nishikori in Brisbane but not before taking the 2014 U.S. Open finalist to three tight sets.
NICK KYRGIOS
Age: 23
Nationality: Australian
World ranking: 51
Titles: 4
Best Grand Slam performance: Quarter-finals of the 2014 Wimbledon and 2015 Australian Open
Best performance at Melbourne Park: Quarter-finals, 2015
Kyrgios showed the world his potential with the extraordinary upset of Rafael Nadal in the fourth round of Wimbledon in 2014 but the mercurial Australia has faced perennial criticism for his attitude, behaviour and commitment.
The local hope was handed a brutal draw with a tough opening clash against big-serving Canadian Milos Raonic and a probable second round meeting with 2014 champion Stan Wawrinka.
DENIS SHAPOVALOV
Age: 19
Nationality: Canadian
World ranking: 27
Titles: None
Best Grand Slam performance: Fourth round at the 2017 U.S. Open
Best performance at Melbourne Park: Second round, 2018
The former Wimbledon junior champion had a breakthrough 2017 when he beat Argentine Juan Martin del Potro and Nadal in back-to-back matches on his way to the semi-finals at the Canada Masters and also reached the U.S. Open fourth round.
The baby-faced left-hander is yet to win anything but reached a career-high ranking of 23rd in the world last year and is the youngest player in the top 100.
CHUNG HYEON
Age: 22
Nationality: South Korean
World ranking: 25
Titles: None
Best Grand Slam performance: Semi-finals of the 2018 Australian Open
Best performance at Melbourne Park: Semi-finals, 2018
The bespectacled South Korean took out Zverev, Djokovic, Tomas Berdych and Gael Monfils at Melbourne Park last year during his stunning progress to the Australian Open last four.
He has yet to win a title and has had a poor start to the year but could put an end to any top player's progress with his relentless court coverage and flexibility.
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