Second seed Aryna Sabalenka reached the US Open semi-finals for the third successive year with a dominant win over Chinese 23rd seed Zheng Qinwen.
Sabalenka, who learned earlier this week she will be the new world number one after the tournament, won 6-1 6-4.
The 25-year-old from Belarus has never gone on to play in the New York final.
Sabalenka will meet the winner of the last quarter-final between Wimbledon champion Marketa Vondrousova and American Madison Keys.
Czech ninth seed Vondrousova and Keys, who was the 2017 runner-up at her home Grand Slam, play in Wednesday's night session, which starts at 19:00 local time (00:00 BST, Thursday).