Karen Khachanov held his nerve in a dramatic fifth-set decider to end the debut run of young American Sebastian Korda and progress into the Wimbledon quarter-finals.

In a back-and-forth encounter, where there were an extraordinary 13 breaks of serve in the last set, it was the Russian who prevailed in three hours and 49 minutes to win 3-6 6-4 6-3 5-7 10-8.

The 25th seed equalled his best ever showing at a grand slam, after he also made the last eight at Roland Garros in 2019, and in the process denied his opponent victory on his 21st birthday.

Korda had beaten seeds Alex De Minaur and Dan Evans to reach the last 16, and a superb backhand winner earned the birthday boy a break in the fourth game of the opener, which he went on to take.

Khachanov turned the match around in the second set and Korda began to struggle a bit physically as the Russian took a two-sets-to-one lead.

The American looked to be heading out when Khachanov moved an early break ahead in the fourth set but Korda showed why he is such an exciting talent by digging in and forcing a decider.

The fifth set was one of the more wild ones played at Wimbledon, with Khachanov failing to serve out the match three times before he finally made it across the line.

Talking about the last set, the Russian, who next faces Denis Shapovalov, said: "I would say it's not common, but it is what it is with the nerves.

"I think this year I had very close matches like this and, for me, it's one of the most important wins, I would say, during the year because, at the end, to pull it off, this is where it counts.

"The most important thing is to win, it doesn't matter how. I'm super happy about it."

Korda insisted his birthday had not been spoiled despite how close he came to victory in his first five-set match.

He said: "I'm still super happy with how the whole tournament and today was. I fought my hardest. I don't know what was happening out there. We just couldn't hold serve.

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

"Ever since I decided to play tennis I always dreamed about having my birthday here at Wimbledon. I knew if I would have my birthday here, I'd have a really good week. Had my first birthday here. Hopefully many more. It was an awesome day."