Novak Djokovic has pronounced himself fit and raring to go in search of his fifth Australian Open title after overcoming a bout of illness that had prompted social media users to suggest he was in doubt for the tournament.

Djokovic had cancelled a practice session and news conference on Saturday, which prompted social media to go into a tailspin, though the 27-year-old dispelled those rumours.

"I had tough couple of days but it's all behind me now. I'm ready for the Open," he said after a practice session on Rod Laver Arena. "Little bit with the flu and stomach. But I carried that already from the Middle East. But now it's good. It's passed."

I had tough couple of days but it's all behind me now. I'm ready for the Open

Novak Djokovic, World number one

The news the affable Serb had overcome his illness was a relief for the organisers, with the world number one a crowd favourite at Melbourne Park.

He has won three of the past four finals and lost to eventual champion Stanislas Wawrinka last year in an epic quarter-final that finished 9-7 in the fifth set.

He is scheduled to play Slovenian qualifier Aljaz Bedene in their first round match on Tuesday.

Del Potro ruled out

Meanwhile, former US Open champion Juan Martin del Potro has withdrawn from the Australian Open due to a lingering wrist injury that he was concerned could cause him further damage if he played the season opening grand slam.

The 26-year-old Argentine played just four tournaments last year after he injured his left wrist and made his comeback earlier this week by reaching the quarter-finals in Sydney but decided it was too risky to play at Melbourne Park.

Serena Williams enters the Australian Open as a strong favourite to lift the Daphne Akhurst Memorial Cup but is all too aware that a sixth Melbourne Park title has now eluded her for five years.

"I've been going for number six for a number of years now," the world number one said. "It would be really special for me. I would be really happy. I want it I think more than anyone else here. But that doesn't mean I'm going to get it, so I'll have to fight hard to get it."

The 33-year-old American won her last Australian Open in 2010 and while she missed the 2011 event due to injury, she has not advanced past the quarter-finals in the past three years.

Source: Reuters