Daniil Medvedev dethroned defending champion Carlos Alcaraz in a US Open thriller on Friday to set up a repeat of the final from two years ago against 23-time Grand Slam champion Novak Djokovic.

Medvedev defeated Alcaraz 7-6 (7/3), 6-1, 3-6, 6-3 to reach his fifth major final and stop Alcaraz in his quest to become the first back-to-back men's winner in New York since Roger Federer in 2008.

"I said I needed to play 11 out of 10. I played 12 out of 10, except from the third set," said Medvedev.

"He (Alcaraz) is honestly just really unbelievable. To beat him you need to be better than yourself and I managed to do it."

Medvedev now meets Djokovic on Sunday as the 36-year-old Serbian star once more goes in search of a record-equalling 24th Grand Slam title to crown his return to world No 1 next week.

The third-seeded Medvedev won his lone major at the 2021 US Open when he foiled Djokovic in his bid for a calendar Grand Slam.

He produced a scintillating performance against Alcaraz, avenging a lopsided loss to the Spaniard in the Wimbledon semifinals in July.

Medvedev held his nerve under constant pressure from Alcaraz in the opening set, elevating his level in tie-break to claim the final four points.

Alcaraz didn't face a single break point in the first set, but Medvedev totally dominated the second set – dropping just two points on serve and breaking the top seed twice.

The Spaniard kept his hopes alive with a break in the fourth game of the third set enough to extend the match to a fourth set.

He saw three break points come and go at 1-1 before Medvedev administered the fatal blow with a superb backhand return, breaking for a 4-2 lead.

A routine hold moved Medvedev to the cusp of victory, which he eventually sealed after an epic final game in which Alcaraz saved three match points but also failed to convert three break points.

DJOKOVIC OUTWITS SHELTON

Djokovic ended the run of 20-year-old Ben Shelton earlier on Friday, winning 6-3, 6-2, 7-6 (7/4) to advance to his 10th US Open final in 17 appearances.

"Another Grand Slam final. I cannot be happier with where I am," said Djokovic, who missed last year's tournament at Flushing Meadows because of his refusal to be vaccinated against Covid-19.

Djokovic is attempting to become the oldest men's champion in New York in the Open era, which would also see him match Margaret Court's all-time mark for most major singles titles.

The Serbian has now won 22 of his last 23 Grand Slam semifinals. He captured the last of his three US Open titles in 2018.

Djokovic has reached the final at all four majors in the same year for the third time. He will try to claim three Grand Slams in the same season for the fourth time in his career.

"I'm obviously over the moon with the results so far on Grand Slams," said Djokovic.

"Playing in all four finals of all four Slams in a season is amazing. It's the highest achievement I can think about when I start the season.

"That's what I dream about, that's what I really wanted, that's where I want to be, in this kind of position."

Djokovic's only Grand Slam loss this year came at Wimbledon when he was beaten by Alcaraz in five sets.