Daniil Medvedev tore up the US Open script by knocking out defending champion and world number one Carlos Alcaraz in the semi-final.
The 27-year-old Russian, the Flushing Meadows champion in 2021, will face Novak Djokovic - the man he beat to win his first and only grand slam so far - in Sunday's final after a shock 7-6 (3) 6-1 3-6 6-3 victory.
The smart money this fortnight had been on another Djokovic-Alcaraz final, a repeat of the Wimbledon epic which the Spaniard won and another chapter in a burgeoning rivalry.
But Medvedev, the world number three, had other ideas and, coming from behind a near flawless serve, looked like he was back to being the player who swept to glory two years ago.
"It's amazing, especially beating someone like Carlos," he said. "I lost easy to him two times this year so I had a lot of doubts.
"I said I needed to play 11 out of 10, and I actually played 12 out of 10, except in the third set. He's pretty unbelievable so to beat him you need to be better than yourself and fortunately I was."
Medvedev has had a love-hate relationship with the US Open crowd over the years.
He added: "I have to be honest, the crowd was unbelievable today. We had some crazy points and I felt, let's call it, love to both guys.
"At 5-3 I guess we had some Spanish guys calling out between first and second serves, but they can go to sleep now."
Djokovic, 36, is hunting a fourth US Open title that would see him equal Margaret Court's record haul of 24 Grand Slams and a good measure of revenge on Medvedev.
"He (Djokovic) is always better than the previous time he plays. For example, I beat him in the US Open final, he beat me in Bercy (Paris Masters) in a great match. Carlos beat him in Wimbledon, he beat him in Cincinnati," Medvedev said.
"Novak is going to be his best version on Sunday, and I have to be the best-ever version of myself if I want to try to beat him.
"Novak, when he loses, he's never the same after... It's just a different mentality... So, I have to use it knowing that he's going to be 10 times better than he was that day. And I have to be, if I want to still beat him, 10 times better than I was that day."
"To know I'm capable of doing it on the big stage every time you do it one more time brings more confidence," Medvedev added.
"You know you can do it again. You want to do it again. You want to feel this. And at the same time, what is most important is to kind of use it but forget about it and go for the next one."
If the alarm bells had yet to start ringing for Alcaraz when he lost a tight first set on a tie-break, they were surely chiming when he was broken twice in a one-sided second set to slip 2-0 down.
The 20-year-old had never come back from two sets down to win a match in his career so far.
But after two hours of toiling away Alcaraz did engineer his first break of the Medvedev serve, sealing the deal with a superb backhand lob to halve the deficit.
The sixth game of the fourth set proved pivotal, a near 15-minute affair at the end of which Alcaraz missed his volley and Medvedev had the break for 4-2.
At 3-5 down Alcaraz had two break points but Medvedev hung in, only to then double-fault on his first match point.
Alcaraz saved a second and third match point, but Medvedev converted the fourth to reach his third US Open final in five years.
"These kind of matches can happen even if I feel myself (as a) different player, more mature," Alcaraz said.
"I thought that, you know, right now I am better player to find solutions when the match is not going in the right direction for you. But, you know, after this match, you know, I gonna change my mind. I'm not mature enough to handle these kind of matches. So I have to learn about it."
Alcaraz rarely seems to let his frustration get the best of him on the court but admitted that he struggled to keep his temper on Friday, particularly as he was unable to come back in the second set.
But while the semi-final exit was undoubtedly a bitter end to an otherwise terrific North American hardcourt stretch, Alcaraz said he could keep the defeat in perspective.
"I don't think I'm gonna think about this loss for a long time. Of course I have to learn about it. I want to be better," he said.
"You know, these kind of matches help you a lot to be better and grow up in these kind of situations."
Additional reporting: Reuters
