Ons Jabeur has reached her first US Open quarter-final where the world No 5 will take on unseeded Australian Ajla Tomljanovic on Tuesday.
The Tunisian dug herself out of a hole in the first set to defeat Russian Veronika Kudermetova 7-6, 6-4 and book her spot in the last eight.
With the victory, Jabeur became the first Arab woman to reach this stage at Flushing Meadows. The last African woman to reach the quarter-finals in New York was South Africa's Amanda Coetzer in 1998.
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 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 Grand Slam final in London 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 match point 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 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.”
It is the latest piece of history for trailblazer Jabeur, who has already become the first Tunisian and first Arab woman to win a WTA title, to reach the top 10, and to make a Grand Slam quarter-final.
Tomljanovic, who defeated Serena Williams in the 23-time Grand Slam winner's final match, reached her second Slam quarter-final in a row with a 7-6, 6-1 win over Liudmila Samsonova on Louis Armstrong Stadium.
“Just feels really good to back up a win that I think got a lot of attention,” Tomljanovic said. “It's been a really big 48 hours. I didn't really feel like myself today the whole day.
“I 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.”