Karen Khachanov reached the Wimbledon quarter-finals for the first time on Monday with a five-set win over Sebastian Korda who was celebrating his 21st birthday in a tie which set a record for most breaks of serve in a set.

Russian 25th seed Khachanov triumphed over his American rival 3-6, 6-4, 6-3, 5-7, 10-8 and will face Canadian 10th seed Denis Shapovalov for a place in the last four.

A marathon 81-minute final set on Court 18 featured 13 breaks of serve before Khachanov steadied himself to take the victory.

"At least we made some record in some ways," said 25-year-old Khachanov.

"I would say it's not common, but it is what it is with the nerves. When basically you break a couple of times before the fifth set, and then you have, yeah, 13 breaks, it's tough to explain. 

"But on the other side it's easy to explain. When you are returning better you start to read the serves better, and then in play, in the rallies, both of us were more stressed, more tight. 

"This is obvious. You don't need to be hiding that. At the end, the one who deals better with the stress wins the match."

Khachanov will be playing in the last-eight of a Slam for the second time after the 2019 French Open where he defeated Juan Martin del Potro before going down to eventual runner-up Dominic Thiem.

Korda was attempting to emulate his father Petr who was a quarter-finalist at the All England Club in 1998.

The world number 50 came within two points of victory at one stage in the final set.

"I fought my hardest. I don't know what was happening out there. We just couldn't hold serve," said Korda of the error-hit final set.

"We were playing some clutch tennis when we needed it, both of us. Yeah, hats off to him. He played a great match."

Korda, whose sister Nelly won a maiden major golf title at the USPGA Championship on the eve of Wimbledon and claimed the world top ranking, admitted he had been carrying an injury late in the match.

"It's kind of like my butt area," he explained.

"Played a lot of tennis. I'm not used to the grass. I mean, it's my first real tournament on the grass. 

"My body is kind of adjusting to it. It's a pretty painful surface to play on."