Novak Djokovic and Roger Federer stayed on course for a mouth-watering French Open semi-final showdown on Sunday, but only after they survived fourth round scares at a chilly Roland Garros.

Djokovic staged an epic recovery to defeat Italy's Andreas Seppi 4-6, 6-7 (5/7), 6-3, 7-5, 6-3 while Federer, the champion in 2009 and a four-time runner-up, dropped the first set against Belgian lucky loser David Goffin, the world number 109, before claiming a 5-7, 7-5, 6-2, 6-4 win.

World number one Djokovic, bidding to become just the third man to hold all four majors at the same time, and first since 1969, struggled in the cold conditions on Philippe Chatrier court against a player he'd beaten seven times in seven meetings.

"I played very badly, but I won thanks to my fighting spirit," said Djokovic, after a 25th successive Grand Slam match win took him into the Paris quarter-finals for the sixth time.

"He was the better player for the first two sets and I was fortunate to come through. But even at two sets down I still believed I could do it and that's about the only positive I can take. It was one of those days when nothing worked."

77 unforced errors from Djokovic

A lacklustre Djokovic committed 77 unforced errors to 22nd seed Seppi's 81 before pulling through after four hours and 18 minutes.

He will next face either French fifth seed Jo-Wilfried Tsonga or Switzerland's Stanislas Wawrinka, the 18th seed, for a place in the semi-finals.

The 25-year-old Djokovic has never got beyond the semi-finals in Paris and his discomfort on the testing red clay courts was starkly illustrated last year when a 43-match winning run was ended by Federer.

On Sunday, his love-hate relationship with the venue looked set to slump to a new low.

For the first two sets, he was heading for the biggest shock since Rafael Nadal had his perfect 31-match, four-title stretch smashed by Robin Soderling at the same stage in 2009.

But the top seed regrouped as Seppi, who had also played five-set matches in the second and third rounds, wilted.

Victory represented the Serb's third win from two sets to love down after pulling off similar Houdini acts against Federer in the US Open semi-final last year and Wimbledon second round against Guillermo Garcia Lopez in 2005.

"I didn't have a good start in the third and fourth sets. That's the only thing I could have done better," said Seppi, who was playing in his first Grand Slam last 16 match at the 29th attempt.

Federer too in last eight

Federer, the record 16-time Grand Sam title winner, booked his place in a 32nd consecutive quarter-final at the majors.

Contesting his 50th successive Grand Slam tournament, the third seed will take on either Argentine ninth seed Juan Martin Del Potro or Tomas Berdych, the seventh-seeded Czech.

"I didn't know much about Goffin beforehand, but I know him a lot better now," said Federer, who was two points away from going down two sets to love against the Belgian, who used to plaster his bedroom wall with posters of the great Swiss.

The 21-year-old Goffin was bidding to become the first man to reach the last eight on his Grand Slam debut since Alex Radulescu at Wimbledon in 1996.

He was also the first lucky loser - an alternate on standby after being beaten in qualifying - to reach the last 16 of a major since countryman Dick Norman at Wimbledon in 1995.

"I came out of the qualifiers and I played my best tennis in my first three matches. Then playing Roger was the cherry on the cake," said Goffin.

"I won't hide the fact that I had photos of Roger everywhere on the walls of my bedroom. It was like a dream for me playing him here."

The men's fourth round will be completed on Monday when six-time champion Rafael Nadal, who celebrated his 26th birthday on Sunday, meets Argentina's Juan Monaco.

Serb eighth seed Janko Tipsarevic tackles in-form Spanish 12th seed Nicolas Almagro.

Fourth seeded Briton Andy Murray faces French 17th seed Richard Gasquet with David Ferrer, the sixth seed, taking on 20th seed Marcel Granollers in an all-Spanish contest.