American Emma Navarro’s best run in the U.S. Open is over.

Aryna Sabalenka’s quest for mental toughness — and her first title at Flushing Meadows — is very much alive.

Sabalenka overpowered the gritty New York-born Navarro, 6-3, 7-6, in Thursday’s semifinal to get back to the U.S. Open final.

“Even though you guys were supporting her, I was getting the goosebumps,” Sabalenka said in an on-court TV interview. “She’s a really tough opponent and I’m really happy to get through these difficult semifinals.”

Last year, Sabalenka lost to Coco Gauff in the final. For the No. 2 player in the world — who has won the last two Australian Opens — it has marked a long climb back.

She has often cracked under pressure at this point in majors, her 3-5 mark in Grand Slam semifinals not quite up to par with her prodigious talent and impressive power.

But Sabalenka has worked hard on her mental game, not letting her emotions get the better of her as has happened so often in the past.

The Belarusian hit 34 aces, limited Navarro to just 4 of 16 on her second serves and will face either Karolina Muchova or American Jess Pegula on Saturday.

“I don’t really care because today was a good test for me, the crowd cheering for my opponent,” said Sabalenka. “I’m ready to face whoever. Lesson from last year, and I really hope I’m going to do a little better than last year.

“I was like, ‘Aryna you have to stay focused on yourself.’ I was thinking, ‘No, not this time.’ ”

Navarro — born in Manhattan to billionaire banker Ben Navarro — has displayed a steely resolve during this U.S. Open, knocking off the defending champion in the fourth round and Paula Badosa in the quarterfinal. And she showed well in a high-quality match that saw scores on 21 straight first serves in the second set.

But she couldn’t stop the 26-year-old Sabalenka.

Navarro came in leading the WTA in hardcourt wins this year with 31. She never flinched Thursday, but was undone by an ineffectual second serve while being unable to do enough on her first to open that up.

As for Sabalenka, she is on the best run of her career. She has won 26 of her last 27 hardcourt major matches.

Since the start of last year, Sabalenka has won the Australian Open twice, made the semis in Wimbledon and the French and now reached back-to-back finals in Flushing.

Sabalenka broke Navarro’s first service game thanks to an unforced error.

She put her power on display right from the start. Hitting big more often than not, she ground out the first set, 6-3.

Navarro needed to go bigger on her first serve and go to Sabalenka’s backhand.

The latter was averaging a dominating 78 mph on her forehand, and she hit a monster 86 mph to give her a break point that she converted to go up 3-2.

Sabalenka went up 4-2 and held to go up 5-3. But Navarro showed her nerve to take the next three games.

With Sabalenka now serving down 6-5 — and the partisan crowd exhorting her American foe — she drilled a 101-mph ace for advantage and let out a guttural roar. Her backhand clinched it and forced a tiebreak.

Navarro went up 2-0 thanks to Sabalenka’s double fault, after which the latter gave a sarcastic thumbs up to her coaches box.

But she took the next six points — the third an 18-shot rally that she put away with a backhand, the fourth a big serve and the fifth an absolutely filthy forehand.

The sixth was a slick drop shot that had Navarro racing to return, and then vulnerable to the passing shot. It set up four match points and she only needed one, a spike that ended it.