Ons Jabeur rolled into the U.S. Open women’s final Thursday night, while Iga Swiatek had to rally to get there, a comeback befitting the No. 1 women’s player in the world.

Swiatek seemed on the brink of defeat before storming back to win the last four games and beat Aryna Sabalenka 3-6, 6-1, 6-4. The top-seeded Pole bounced back after losing the first set, then after falling behind 4-2 in the third, she fought back to claim 16 of the final 20 points.

“Honestly I knew I had nothing to lose, basically. Aryna served really well, better than our other matches. Mentally these two games I lost helped me get back on ground,” the 21-year-old Swiatek said. “I backed out a little bit on the return, but I just went all-in and the balls I played went in.

“I feel like my level of trust should be for sure higher, but I’m the person who is not yet trusting myself. I feel like I trust myself on clay, and here I tried to accept I am still not trusting myself and have to prove myself against heavy hitters. I don’t care. It’s not like it’s a negative. Having doubts is not nice, but I found it pretty motivating.”

It’s a stunning admission considering Swiatek has been dominant as the world’s top player this year, reeling off 37 straight wins at one point and winning six titles. But after losing the first set Thursday, a quick trip to the locker room for a bathroom break helped her reverse the momentum.

“I needed to get it together,’’ Swiatek said.

When asked what she told herself to get going, she quipped: “It was more what I did. I felt lighter. Sorry, that’s disgusting.”

But Swiatek did acknowledge that she has gotten mentally tougher and is in a better headspace than she was earlier in her career, and that helped her gut out a tough victory.

“When I was younger all I could do in bathroom when I was down was cry,” Swiatek said. “This time I can actually think about what to change, problem solve.”

The sixth-seeded Sabalenka fell to 0-3 in Grand Slam semifinals.

Swiatek, who won the French Open this spring, will take on the fifth-seeded Jabeur looking to become the first woman to claim multiple majors in the same season since Angelique Kerber in 2016.

Earlier, Jabeur, who lost in the Wimbledon final, made short work of Caroline Garcia 6-1, 6-3. The Tunisian is the first African or Arab woman to reach the final at Flushing Meadows in the Open Era.

“I’m definitely going to learn from all the finals I played, especially the last one at Wimbledon,” Jabeur said. “I’m going to give it all, definitely going for the title.

“[It] feels more real, to be honest with you. At Wimbledon I was just living the dream, and I couldn’t believe it. … But now I hope I’m getting used to it. [I’m] just happy I backed up the results in Wimbledon and people are not really surprised I’m in the finals.”

Jabeur snapped her French foe’s 13-match winning streak (which included a quarterfinal victory over American Coco Gauff) and improved to 6-0 in semifinals this year.

“I don’t have a good record with quarters; but now the semis, we’re very good buddies,” Jabuer said with a chuckle. “Apparently I like playing finals.

“I remember saying that I want to be a top 5, I wanted to win a Grand Slam [tournament], and I wanted to qualify for the Masters. … Check. Check. There’s one more [I’m] going to check hopefully soon.”

Jabeur broke Garcia right out of the gate.

The 17th-seeded Garcia had lost consecutive games just once this entire tourney, and hadn’t even faced a set point, much less dropped one. But Jabeur broke her three times in a first set in which Garcia look skittish, with 14 unforced errors.

Now Jabeur will face Swiatek to cap her U.S. Open run, which is a big enough deal back home that soccer-mad Tunisia tuned into her quarterfinal Tuesday instead of Paris Saint-Germaine’s Champions League win over Juventus.

“In Tunisia it’s all about soccer. But people were not watching the game, they were watching my game, which is impressive to me,” Jabeur said. “I was surprised.”