NEW YORK -- Emma Navarro rode a stunning turnaround right into her first Grand Slam semifinal, beating Paula Badosa 6-2, 7-5 at the US Open on Tuesday to follow up her upset of defending champion Coco Gauff.
Trailing 5-1 in the second set and three points from having to go to a deciding third, Navarro won the next four points to stay alive, starting a stretch in which she captured 24 of the final 28 points of the match.
"I think things weren't looking great there in the second set, but just tried to be really tough, stick in there, make her hit one more ball," Navarro said. "I felt like if I could scrap out a few longer points, maybe put some pressure on her, I felt like I could come back and maybe close it out in two sets.
"Happy with how I was able to do that."
Navarro, the No. 13-seeded American who had never even won a match in the main draw of her home major before this year, will face No. 2 Aryna Sabalenka in Thursday's semis.
The 23-year-old Navarro, who ousted the No. 3-seeded Gauff on Sunday in the fourth round, ran through the first set in 29 minutes before the No. 26-seeded Badosa opened a 5-1 lead in the second.
But when Navarro broke the Spaniard in the next game, the player who leads the WTA Tour with 18 wins in three sets had a feeling she might not need to play a third.
"I felt like, even though she was up 5-1, 5-2 after that game, I felt like she wasn't totally confident in her ability to close out that set," Navarro said. "So I felt like if I could push back a little bit and make her think a little bit on her service game, maybe I could sneak my way back in there."
She did, taking six straight games with some help from Badosa, who said she was a "disaster" while dealing with the pressure of trying to reach her first Grand Slam semifinal.
"I never had the momentum in this match. I played four or five games OK. It was 5-1, but I never felt myself on the court," Badosa said.
"I lost, I don't know, 20 points almost in a row. It's very weird for me because I'm quite a consistent player, so I wasn't expecting that either."
Navarro also beat Gauff in the fourth round at Wimbledon before losing to eventual runner-up Jasmine Paolini in the next round, a 6-2, 6-1 rout in less than an hour.
But the 2021 NCAA singles champion at Virginia was ready for this matchup between New York natives, jumping on Badosa to win the first three games, then seizing the opening Badosa gave her late.
Navarro became the sixth player in the last 40 years to reach the US Open semis without a previous main-draw victory in the tournament, a list that includes recent champions Bianca Andreescu in 2019 and Emma Raducanu in 2021.
It has been a career year for Navarro, who reached the third round or better at all four Grand Slams after never having advanced beyond the second round of a major.
She is the third former women's college player in the past 40 years to make the semifinals at Flushing Meadows, following Oklahoma State's Lori McNeil in 1987 and UCLA's Jennifer Brady in 2020.
Her victory ended an impressive summer season by Badosa, who entered Tuesday having won 24 of her past 30 matches since May's tournament in Rome, highlighted by a WTA 500 title in Washington and a semifinal appearance in Cincinnati before her run in New York.
ESPN Stats & Information and The Associated Press contributed to this report.