Aryna Sabalenka, touted to be the new World No. 1 at the end of the US Open, cruised into the quarterfinals with an easy win over Daria Kasatkina 6-1, 6-3 on September 4.
In two major upsets, 2022 runner-up Ons Jabeur was ousted by Qinwen Zheng in straight sets while Madison Keys triumphed over compatriot Jessica Pegula 6-1, 6-3.
Qinwen will face Sabalenka in the quarters while Keys will battle 2023 Wimbledon winner Marketa Vondrousova for the coveted final 4 spot.
Meanwhile, in the men's singles draw Alexander Zverev outlasted sixth seed Jannik Sinner in a gruelling 5-set thriller to set up a quarters clash with defending champion Carlos Alcaraz.
Alcaraz made little work of Matteo Arnaldi in their Round of 16 meeting, defeating him 6-3, 6-4, 6-4.
2021 USO winner Daniil Medvedev overcame a challenge in the form of Alex de Minaur in four sets and will meet friend Andrey Rublev to fight for a spot in the semifinals.