Home favorite Coco Gauff and world number two Elena Rybakina sailed into the US Open quarter-finals on Monday, while China's Zheng Qinwen mounted another extraordinary fightback to upset six-times Grand Slam champion Iga Swiatek.
Fourth seed Gauff outclassed compatriot Iva Jovic 6-1 6-4 to set up a clash with fellow French Open champion Mirra Andreeva for a place in the semis.
"Mirra is someone that I always have tough matches with," Gauff told reporters. "She's obviously in a different mindset now at the top of the game coming off of a Grand Slam win ... it's going to be a really athletic, tough match."
Gauff is the sixth American player into the quarters, joining Jessica Pegula, Emma Navarro, Frances Tiafoe, Alex Michelsen and Ben Shelton.
Rybakina continued her quest for a third major title with a 6-1 6-4 win over former US Open champion Naomi Osaka, who was hampered by an Achilles tendon injury that had flared up in the previous round.
The victory leaves second seed Rybakina one win away from becoming world number one for the first time, with Olympic champion Zheng awaiting her in the quarters.
The win was another encouraging sign for Rybakina, who had arrived in New York with questions over her fitness after retiring from the Cincinnati Open in the build-up to the tournament.
"Preparation wasn't that great," she told reporters, according to Reuters. It's an amazing progress. I'm really glad how everything worked out."
Zheng has become something of an escape artist at Flushing Meadows.
After coming back from a 0-5 deficit in the deciding set against third-round foe Madison Keys, she let the first five games slip through her fingers in 20 minutes against 2022 champion Swiatek.
However, she clawed her way back into the match and collapsed to the court with her face in her hands after sealing the win on the fourth match point.
Zheng is the first qualifier since Emma Raducanu in 2021 to reach the quarter-finals of the women's draw, as she battles back from a chronic elbow injury.
Andreeva's entertaining match against Anastasia Potapova ended on a sour note as the Austrian went down injured in the final game.
Potapova valiantly retook the court but could not prevent the inevitable as Andreeva sealed the 5-7 6-4 6-3 win with a backhand strike before going across the net to hug her opponent.
The evening session in the men's draw was not short on drama.
At Louis Armstrong Stadium, Karen Khachanov fought back to claim a 7-5 4-6 6-7(6) 6-1 6-4 win over 20-year-old American Learner Tien, while on the Grandstand court Botic van de Zandschulp emerged victorious after a five-hour marathon against Arthur Gea.
The 21-year-old Gea had been one point away from becoming the first lucky loser in Grand Slam history to reach the quarter-finals, before his Dutch opponent engineered a 3-6 6-7(0) 7-6(7) 7-6(3) 6-4 comeback win.
Earlier on Monday, Belgium's Alexander Blockx dispatched Argentine 24th seed Francisco Cerundolo 6-3 4-6 7-5 7-5 to reach his first Grand Slam quarter-final.
