Andy Murray survived a scare from Fabio Fognini as the defending champion scraped his way into the Wimbledon last 16 along with title rival Rafael Nadal on Friday.

Murray didn't have it all his own way against Fognini, but the world number one eventually subdued the eccentric Italian 6-2, 4-6, 6-1, 7-5 to secure a 10th successive appearance in the Wimbledon fourth round.

In a tetchy Centre Court clash, Murray complained about Fognini taking too long between points as the 28th seed, who was given a point penalty for a visible obscenity, shrugged off a mid-match injury to push the Scot to the brink.

Murray had to save five set points to avoid being forced into a deciding set, reeling off five successive games to secure his 105th win on grass and remain on course for a titanic semi-final showdown against Nadal.

The 30-year-old, who faces France's Benoit Paire for a place in the quarter-finals, is bidding to become the first Briton to successfully defend a Grand Slam title since Fred Perry at Wimbledon from 1934-1936.

"Obviously the end of the match was tense. It was a very up and down match," Murray said.

"I didn't feel like it was the best tennis, but I managed to get through. I was pleased to get off in four sets."

Having won his 10th French Open crown without dropping a set last month, Nadal has made the switch from clay to grass with ease.

His 6-1, 6-4, 7-6 (7/3) win against Russian 30th seed Karen Khachanov equalled the Spaniard's personal record of 28 successive sets won at Grand Slams, a blistering streak dating back to this year's Australian Open final.

Nadal's second and most recent Wimbledon title came in 2010 and the 15-time major winner hasn't been past the fourth round for six years.

But world number two Nadal is in formidable form heading into only his second fourth round tie in his last five visits to Wimbledon.

His opponent is 16th seed Gilles Muller, who defeated Aljaz Bedene 7-6 (7/4), 7-5, 6-4 to reach the last 16 for the first time at the age of 34.

"I played fantastic for a set and a half but it got tougher after that. He started to hit stronger so I was happy to get through in three sets," Nadal said.