Madison Keys has confidently swatted aside Wimbledon champion and ninth seed Marketa Vondrousova 6-1 6-4 to reach the US Open semi-finals.
The 17th-seeded American needed just 86 minutes to ensure progress, fending off all nine break points she faced across the match at Arthur Ashe Stadium on Wednesday night (Thursday AEST).
The 2017 finalist suffered a handful of early exits from her domestic grand slam in recent years but has excelled in the 2023 edition and appeared right at home in prime time under the Flushing Meadows bright lights against Vondrousova.
The match got off to an unusual start as the chair umpire was forced to stop play midway through the first game for several minutes when a spectator needed medical attention.
Keys was clearly not rattled by the incident and began her demolition once play resumed, breaking Vondrousova to love in the second game and converting on another break point chance with a fine forehand winner in the fourth.
Czech Vondrousova upped her level across the board in the second set but was unable to seize the momentum and left to rue missed opportunities as she failed to convert on five break points in the eighth game alone.
"I just love it here. I love playing here. In front of a home crowd you can never feel like you can't get out of any situation," Keys said.
"I knew I was going to have to keep trying to get to the net, be aggressive."
The 28-year-old next faces second seed Aryna Sabalenka, who earlier dispatched China's Zheng Qinwen by the same 6-1 6-4 scoreline in just over an hour.
Sabalenka became the first woman to reach the semi-finals of all four grand slams in the same year since Serena Williams in 2016.
"I'm super proud of myself and my team that we have been able to adjust to different conditions, different courts. We were able to bring this consistency in my game," she said.
"Yeah, this is something I'm really proud of, and it's just unbelievable and I'm just super happy right now that I'm being able to do this."
Sabalenka, who is going to be the world No.1 in the WTA rankings next week because of the fourth-round loss of Iga Swiatek, still has not dropped a set in New York.
The No.2-seeded Belarusian cruised through her last-eight clash in searing heat that prompted a partial closing of the stadium roof to provide more shade.
"I just gave myself another opportunity to do better in the semis," said Sabalenka, who won her lone major at the Australian Open in January.
"I still have things to do in New York. I'll think about being the world No.1 after the US Open."
While "super happy" with the top ranking, she said it wasn't a big change.
"You know, I mean, I have been No.2. Now I'm No.1. It's just a difference of position in the draw. I still have to bring my best tennis. I still have to play my best. People will try to chase me and get me.
"But it's just an extra motivation for me. You know, seeing them, like, really trying their best to beat me, it's, like, an extra power and energy for me to keep playing, keep pushing, keep getting better."
Thursday's other semi-final will feature American No.6 seed Coco Gauff and 10th-seeded Czech Karolina Muchova.