Defending champion Coco Gauff came back from a set down to beat Ukrainian Elina Svitolina and reach the fourth round of the US Open.

American third seed Gauff’s bid to become the first woman to defend the title since Serena Williams in 2014 is still alive after a hard-fought 3-6 6-3 6-3 victory.

“This win means a lot,” Gauff said. “I knew today was going to be a tough match. Every time I play Elina, she’s a fighter. I knew I had to bring my best tennis.”

She will face compatriot Emma Navarro after the 13th seed claimed a 6-4 4-6 6-3 win over Ukraine’s Marta Kostyuk.

The two Americans met in the fourth round of Wimbledon this year, with Navarro causing a shock on Centre Court.

“I feel like that match at Wimbledon I think I mentally just literally collapsed on the court. I was very frustrated, and she played well,” said Gauff.

“I have to expect her to play her best tennis, and I just need to know that I need to bring it and mentally be there from the beginning to the end.”

Meanwhile, last year’s runner-up Aryna Sabalenka fought back from a set down to beat Russian Ekaterina Alexandrova 2-6 6-1 6-2 in a match that finished at 1.49am local time in New York (06:49 BST).

The late-night finish was a result of Friday’s day session on Arthur Ashe Stadium filtering into the evening slot, with Frances Tiafoe and Ben Shelton playing out a five-set thriller before the men’s defending champion Novak Djokovic suffered a surprise defeat by Alexei Popyrin.

“Thank you all for staying that late guys. For real, you’re the best. I hope you’re going to get a good sleep,” said Sabalenka, who arrived on court after midnight.

“I was praying they’re were not going to play so long.

“It was tricky but I just stayed with my team, tried to relax and pretended that the match was going to be in five hours instead to chill.”

Svitolina sent the crowd on Arthur Ashe Stadium into a nervous silence when she served out the first set after breaking for a 5-3 lead.

But it was Gauff who struck first in the second, converting her break point with a brilliant cross-court forehand winner.

With her confidence boosted and the crowd behind her, the 20-year-old American held serve twice more and let out a huge roar as she forced a decider.

Gauff’s momentum continued as she dominated Svitolina’s serve, breaking twice to surge into a 4-1 lead.

But she then failed to convert three match points while trying to serve out the match before eventually securing the win by breaking Svitolina to love in the next game, screaming to the crowd in delight.

Sabalenka, who replaced Gauff as number two in the world rankings earlier this month, also got off to a slow start.

Alexandrova, the 29th seed, earned two successive breaks in the first set before serving it out – much to Sabalenka’s frustration.

But the Belarusian regained her composure to break first in the second and it was plain sailing from there.

“She played incredible tennis in the first set, it was really tough to change that. I’m really happy I was able to turn it around,” Sabalenka said.

The Australian Open champion will face Belgium’s Elise Mertens, who won 6-7 (5-7) 7-5 6-4 against American 14th seed Madison Keys.

Elsewhere in the women’s draw on Friday, Spaniard Paula Badosa saved a match point as she came from behind to beat Romania’s Elena-Gabriela Ruse.

Badosa, seeded 26th, needed a match tie-break to book a spot in the fourth round for the first time with a 4-6 6-1 7-6 (10-8) victory.

The former world number two said she was playing “maybe at one of the best levels” of her career after an injury-hit year.

“It means so much, and after what I’ve been through the last year, for me it’s very special to already be on this level,” said Badosa, who has constant pain in her back after a stress fracture.

“At the beginning of the year I was obsessed – I wanted to have the comeback of the year, like no matter what.

“I’m back at the top. For me it means a lot because it’s where I want to be.”

Badosa, 26, will take on Wang Yafan next after the Chinese player overcame former world number one Victoria Azarenka 6-4 3-6 6-1.

Olympic champion Zheng Qinwen‘s bid for a first Grand Slam title remains on course after she cruised past German Jule Niemeier with a 6-2 6-1 victory.

Zheng will play Wimbledon semi-finalist Donna Vekic, who moved past American Peyton Stearns 7-5 6-4.