Serena Williams is two wins away from her record 23rd Grand Slam title.
Williams, the top seed in the U.S. Open women's singles draw, knocked off No. 5 Simona Halep 6-2, 4-6, 6-3 to advance to the semifinals.
Halep won a tense second set, but Williams dominated the third to advance to the 11th U.S. Open semifinal of her career.
Wednesday's night session will conclude with a men's quarterfinal between Stan Wawrinka and Juan Martin del Potro.
See below for a closer look at Wednesday night's results.
For news and results from Wednesday's day session, including victories by Karolina Pliskova and Kei Nishikori, check out SI.