MELBOURNE: Novak Djokovic bids for an unprecedented third straight Australian Open title from Monday, with growing rival Andy Murray and the great Roger Federer shaping as his biggest challenges.

Argentina’s Juan Martin Del Potro is the only man besides Djokovic, Rafael Nadal, Federer and Murray to win a Grand Slam tournament since 2005, but the Serb said there were plenty of others who could threaten their dominance.

“It’s probably expected that the three of us, and Nadal of course, would still be main candidates to win all the major titles,” Djokovic said.

“But, you know, I wouldn’t underestimate Del Potro, (Jo-Wilfried) Tsonga, (David) Ferrer, (Tomas) Berdych, anybody who is in the top 10.

“I’m sure there’s new young players coming up like (Bernard) Tomic, (Grigor) Dimitrov, (Milos) Raonic.

“I don’t think it’s nice for me to predict that us three will be champions of all Grand Slams this year.”

However, the odds favour Djokovic who is targeting a third straight Australian title, a feat which has not been achieved in the professional era.

Nadal is not playing due to illness, robbing Melbourne Park of a repeat of last year’s epic final, when Djokovic finally tamed the Spaniard at 1:40 am after a record, 5hr 53min final which left him with bleeding toes.

But Djokovic will face a stiff challenge from the newly assertive Murray, fresh from his first Grand Slam win and keen to avenge his final and semi-final defeats to Djokovic in Melbourne in 2011 and 2012.

Also pressing hard will be Federer, holder of an unmatched 17 Grand Slams and still hungry for more even though, at the age of 31, he is conceding six years to his younger rivals.