Australian Open: Novak Djokovic beats Gilles Simon in last 16

Defending champion Novak Djokovic (right) upped his game in the final set

Defending champion Novak Djokovic survived a scare against Gilles Simon to reach the last eight of the Australian Open in Melbourne.

Five-time champion Djokovic made 100 unforced errors but prevailed 6-3 6-7 (1-7) 6-4 4-6 6-3 after four hours and 32 minutes on Rod Laver Arena.

Djokovic, 28, is through to his 27th consecutive Grand Slam quarter-final.

Four-time champion Roger Federer was in vintage form in beating Belgium's David Goffin 6-2 6-1 6-4.

Djokovic plays Japan's Kei Nishikori in the last eight after the seventh seed beat Jo-Wilfried Tsonga 6-4 6-2 6-4, while third seed Federer plays Tomas Berdych.

The Czech sixth seed came through a testing encounter against Spain's Roberto Bautista Agut 4-6 6-4 6-3 1-6 6-3.

'Just happy to get through'

"Playing against a player like Gilles you can expect a lot of rallies," said Djokovic, who is also through to his ninth successive Australian Open quarter-final.

"He is always making you play an extra shot. I made a lot of unforced errors today but he was fighting, he was playing well, physically it was very demanding and I'm just happy to get through this one."

Two breaks were enough for Djokovic to win the first set but the 10-time major champion spurned 11 break points in the second, losing the tie-break 7-1.

Djokovic broke twice again in the third but dabbed two limp drop-shots into the net when serving to stay in the fourth set before missing a backhand to send the contest to a decider.

But Djokovic raised his game at the decisive moment, racing into a 4-1 lead in the fifth and serving out for the victory after Simon had saved two match points.

'No more drop-shots!'

When a spectator shouted out during Djokovic's on-court interview, the defending champion asked him to repeat what he had said.

When the member of the crowd repeated "no more drop-shots", the Serb shrugged and replied: "I hate to say it, but you're absolutely right."

Djokovic's tally of unforced errors is not a record - Yevgeny Kafelnikov hit 112 in defeating Fernando Vicente at the 2000 French Open.

On the plus side, Djokovic equalled Jimmy Connors' career mark of consecutive quarter-finals - only Federer has more with 36.

Federer sublime

Federer won in Melbourne in 2004, 2006, 2007 and 2010 but was knocked out in round three last year

Seventeen-time major champion Federer, 34, barely put a foot wrong against 15th seed Goffin in the night match on Rod Laver Arena.

Federer raced through the first two sets in 50 minutes, hitting winners on both flanks and showing some beautiful touches at the net.

Goffin did finally break Federer in the third, but the Swiss wrapped up the match in an hour and 28 minutes, finishing with 39 winners and losing only 15 points on serve.

"I'm pleased with how I played," said Federer. "David normally gives me a hard time in practice so I was surprised at how well I went."

Nishikori surprised

Kei Nishikori also reached the last eight in Melbourne in 2012 and 2015

Nishikori broke ninth seed Tsonga's serve five times while the Frenchman hit eight double-faults in a flat display.

"Today was one of the best matches I've had this week," said Nishikori, a US Open finalist in 2014.

"I'm surprised that I broke him early every set. I was returning well, so that made it tough for him to have a good serve all the time."

Nishikori, 26, has never reached the semi-finals in Melbourne and trails Djokovic 5-2 in head-to-heads.

Hewitt's final farewell

Australian Lleyton Hewitt bowed out of professional tennis when he and compatriot Sam Groth lost their men's doubles match 6-4 6-2 to American Jack Sock and Vasek Pospisil of Canada.

Hewitt, who lost to Spaniard David Ferrer in the second round of the singles, bows out at the age of 34, having won two Grand Slam titles and helping Australia lift the Davis Cup twice.