Tunisian fifth seed Ons Jabeur dug herself out of a hole in the first set to defeat Russian Veronika Kudermetova 7-6(1), 6-4 to book her spot in the US Open quarter-finals for the first time.
Jabeur found herself trailing 5-2 as the 18th-seeded Kudermetova made a fast start with pinpoint backhand that ran the Wimbledon runner-up ragged in the night's final match at the Arthur Ashe Stadium.
But the 28-year-old managed to find her range to start dominating the baseline rallies and after levelling things at 5-5 she dictated terms in the tiebreaker to take the frame.
Jabeur, who lost the Wimbledon final to Kazakh Elena Rybakina, had to dig deep again to hold serve at the start of the second set but then got the crucial break in the fourth game to nose ahead.
With Jabeur serving for the match, however, Kudermetova got the break back, but the Tunisian breached the Russian's delivery in the next game to close out the contest.
Jabeur let out a huge shriek after Kudermetova sent a forehand long on matchpoint for her 24th unforced error of the night. It was her first win against the Russian in four attempts.
"It was a very difficult match," Jabeur, who will next meet unseeded Australian Ajla Tomljanovic, said in her on-court interview.
"As you can see, at the beginning she was 5-2 up and it's very tough to play her, very frustrating for me, but I had to accept it and keep building. In the end, everything clicked together.
"Hopefully, I can continue to play this way against Ajla."
Tomljanovic also defeated a Russian opponent, Liudmila Samsonova, to reach her maiden quarterfinal at the hardcourt Grand Slam in New York.
"Ajla plays really well and I know it's going to be a physical match. She's going to hit really hard, so I have to be ready physically."
Tomljanovic makes it double delight for Australia
Tomljanovic made it a night to remember for Australian tennis fans, following compatriot Nick Kyrgios into a maiden US Open quarterfinal with a gritty victory over Samsonova.
Shortly after Kyrgios completed a brilliant victory over world number one and 2021 champion Daniil Medvedev at the Arthur Ashe Stadium, Tomljanovic backed up her win over retiring Serena Williams with a 7-6(8), 6-1 triumph at the neighbouring Louis Armstrong Stadium.
“Just feels really good to back up a win that I think got a lot of attention,” Tomljanovic said, referring to her win over 23-time major winner Williams on Friday. “Just felt like it’s been a really big 48 hours.
“I didn’t really feel like myself today the whole day. I don’t know, just felt a little bit drained. After that slow start, I just didn’t want to go out like that. Picked myself up, fought back really hard, played some quality tennis after that.”
Samsonova, 23, came into the evening contest against Tomljanovic on a 13-match winning streak, having lifted titles in Cleveland and Washington D.C. in the leadup to the hardcourt Grand Slam at Flushing Meadows.
The Russian peppered the court with winners and quickly stacked up a 5-2 lead in the opening set.
Tomljanovic, 29, showed lot of resilience to save seven set points and hold serve during a 14-minute marathon ninth game and then successfully defended another setpoint during the tiebreaker to take the opening frame.
The missed opportunities seemed to take a toll on Samsonova’s confidence as her errors mounted and Tomljanovic raced through the second set with two break of serves to reach the quarter-finals at a major for the third time.
“I think my will to go further in this tournament was really strong and I didn’t want to stop just after what happened on Friday night,” she said.
“I thought I deserved more. I definitely wanted to go for more. I dug deep because I felt like I had more left in me.”