The top men's contenders at the Australian Open

Roger Federer will bid to claim a record-equalling sixth Australian Open crown in two weeks' time, looking to defend the title he won last year during a stunning comeback from knee surgery.

Danger lurks at almost every corner, with former Wimbledon finalist Milos Raonic and a resurgent Juan Martin Del Potro, the man who beat Federer for the 2009 US Open title, looming as threats before the quarter-finals.

If fit and firing, 2009 champion Rafael Nadal will be hard to beat, while While Melbourne Park maestro Djokovic will bid for a record seventh Australian Open title.

Most bookmakers see third seed Grigor Dimitrov as the best chance among them to make a breakthrough in Melbourne. On the other hand, fans hoping for a shake-up of the establishment may look to 20-year-old Alexander Zverev after his stellar 2017.

Penpix of top men's contenders at the 2018 Australian Open, which begins at Melbourne Park on Monday.

Roger Federer (Switzerland)

World ranking: 2

Born: August 8, 1981 (Age 36)

Height: 1.85 metres

Plays: Right-handed

Grand slam titles: 19 (Australian Open 2004, 2006, 2007, 2010, 2017, French Open 2009, Wimbledon 2003, 2004, 2005, 2006, 2007, 2009, 2012, 2017 US Open 2004, 2005, 2006, 2007, 2008)

Federer will start as the favourite to retain his Australian Open title and is coming off an extraordinary 2017 season, which also saw him lift a record eighth title at Wimbledon.

The 36-year-old has made an impressive start to the campaign, winning all his four singles matches at the Hopman Cup and combining with Belinda Bencic to win Switzerland their first title since 2001.

His bid for a 20th career Grand Slam title will be aided by the absences of Andy Murray and Kei Nishikori, as well as lingering injuries to other top players in the field such as Rafa Nadal, Stan Wawrinka and Novak Djokovic.

Rafael Nadal (Spain)

World ranking: 1

Born: June 3, 1986 (Age 31)

Height: 1.85 metres

Plays: Left-handed

Grand slam titles: 16 (Australian Open 2009, French Open 2005, 2006, 2007, 2008, 2010, 2011, 2012, 2013, 2014, 2017, Wimbledon 2008, 2010, US Open 2010, 2013, 2017)

The Spaniard enjoyed a stellar 2017, winning Grand Slams at Roland Garros and Flushing Meadows and reclaiming the world number one ranking.

He returns to Melbourne, where he lost a thrilling five-set final to Roger Federer last year, hoping to continue the progress he made in 2017 under coach Carlos Moya, after his uncle and lifelong mentor Toni Nadal decided to step down at the end of last season.

Nadal's preparations for the first Grand Slam of the year have been far from ideal, having not featured in a competitive match since he withdrew from the World Tour Finals in November with a knee injury.

Novak Djokovic (Serbia)

World ranking: 14

Born: May 22, 1987 (Age 30)

Height: 1.88 metres

Plays: Right-handed

Grand slam titles: 12 (Australian Open 2008, 2011, 2012, 2013, 2015, 2016, French Open 2016, Wimbledon 2011, 2014, 2015, U.S. Open 2011, 2015)

After an extended spell on the sidelines with an elbow injury, Djokovic returned with a convincing victory over Dominic Thiem at the Kooyong Classic exhibition event earlier this week.

The 12-times Grand Slam winner is hoping to get back to his best after a forgettable 2017, which included an early exit at the Australian Open and a quarter-final demise at Roland Garros before his season ended in the last eight at Wimbledon in July due to an injury.

Djokovic, who is currently tied with Roy Emerson as the most successful men's singles champions at Melbourne, will launch his bid for an outright record seventh title against American Donald Young in the first round.

Stanislas Wawrinka (Switzerland)

World ranking: 9

Born: March 28, 1985 (Age 32)

Height: 1.83 metres

Plays: Right-handed

Grand slam titles: 3 (Australian Open 2014, French Open 2015, US Open 2016)

The 2014 Australian Open champion is coming off knee surgery and was forced to withdraw from the Tiebreak Tens exhibition event earlier this week with a shoulder injury.

Wawrinka, a three-times Grand Slam winner, made the final four in Melbourne last year before losing to eventual champion Roger Federer in a five-set showdown.

He became the oldest man to reach the Roland Garros final last year at the age of 32 on the back of a few sublime displays of attacking tennis but lost the final to Nadal in straight sets.

Grigor Dimitrov (Bulgaria)

World ranking: 3

Born: May 16, 1991 (Age 26)

Height: 1.91 metres

Plays: Right-handed

Grand slam titles: 0

The Bulgarian returns to Melbourne as one of the in-form players on tour, having enjoyed a pivotal moment in his career when he lifted the ATP Finals trophy at the end of last season.

The world number three started the new year with a semi-final appearance in Brisbane where he was beaten by eventual champion Nick Kyrgios.

It remains to be seen if Dimitrov can improve on his run to the semi-finals in Melbourne last year as he continues to chase his maiden Grand Slam title.

Alexander Zverev (Germany)

World ranking: 4

Born: April 20, 1997 (age 20)

Height: 1.98 metres

Plays: Right-handed

Grand slam titles: 0

Zverev is just 20 but with victories over the "Big Four" and five titles on tour last season, a Grand Slam win seems a possible next step for the German wonderkid.

His top-10 breakthrough came in Rome, where he defeated Novak Djokovic in the final to become the youngest Masters 1000 winner since Djokovic himself won in Miami when 19.

He also became the youngest qualifier at the season-ending ATP Finals since the former US Open winner Juan Martin del Potro in 2008.

Zverev's all-round game makes him a threat at Melbourne next week but he will be tested in the latter stages of the tournament due to his relative inexperience in best-of-five set tennis.

Photographs: Getty Images