Djokovic survives five-set thriller at Australian Open

It was a scare for Novak Djokovic, but the top-ranked player in the world is moving on to the quarterfinals of the Australian Open after a thrilling five-set win over Gilles Simon in the fourth round.

Djokovic has not won five titles at Melbourne Park without being able to negotiate a scrap, however, and despite a string of fluffed drop shots he reasserted his authority in the final set to reach the last eight for a 27th successive grand slam.

The five-time champion Djokovic and the pesky Simon played plenty of long rallies - the longest of which was 37 strokes. "I hope I can make some changes and try to play better".

"I made a lot of unforced errors today but nevertheless he was always fighting".

"I just feel like I'm really confident in my game right now, not against her or against any other opponent", in particular, Williams said.

As he was finishing his on-court interview, a spectator shouted out "no more dropshots!" after the top seed had netted two drop-shots at crucial moments in the fourth set.

Nigel Sears, the coach of Ana Ivanovic and father-in-law of Andy Murray, is expected to be released from a Melbourne hospital later Sunday, a day after he collapsed in Rod Laver Arena during Ivanovic's third-round match. While Djokovic won his 10th straight match over Simon, he only did so after a monumental struggle, losing his serve four times and often looking anxiously at coach Boris Becker in his player's box.

Djokovic tried to destabilise Simon with a number of drop-shots but they were poorly executed, with two in particular at the end of the second set helping Simon force a decider.

Serving for the set, Djokovic twice denied Simon, desperately trying to stay in the set, but the number one's game had deserted him and Simon took the set.

Maria Sharapova is through to the quarterfinals of the Australian Open after a 7-5, 7-5 win over Belinda Bencic of Switzerland.

Two breaks were enough in the first set, but Djokovic was already showing signs of sluggishness.

Serena Williams of the US celebrates during her fourth round match against Russia's Margarita ...

The seventh-seeded Nishikori also reached the quarterfinals at the Australian Open previous year and in 2012.

It's Djokovic's favourite - but there are plenty of rivals for the Serb.

Tenth seed Suarez Navarro rebounded from an opening set battering to beat Daria Gavrilova 0-6 6-3 6-2 and end Australia's interest in the women's draw.

Fatigue and pressure looked to get to Simon by the time Djokovic took a 3-1 lead.

Williams, a 21-time major victor, had a 55-minute, 6-2, 6-1 win over Margarita Gasparyan to set up a big match against Sharapova, a player she has beaten in 18 of their 20 matches.

Sharapova won consecutive matches against Williams in 2004 at Wimbledon and the season-ending championships, but hasn't won since. So, of course, there's going to be a lot of unforced errors piling up.

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