Madison Keys earlier accounted for Swiatek 6-3, 6-4 to take her place in the quarter-finals and register her first win over a reigning World No.1. Swiatek saved four match points, but was far from her best as she exited a second tournament in the North American swing at the last-16 stage.

Keys had failed to take a set off the Pole in two previous meetings but was far more clinical with her powerful returns and groundstrokes. Keys will next face Wimbledon champion Elena Rybakina, who beat Alison Riske-Amritraj 6-2, 6-4 to sail into the quarter-finals.

Wimbledon finalist and fifth seed Ons Jabeur also made her exit, ushered out of the door by Petra Kvitova 1-6, 6-4, 0-6. On the men’s side, World No.1 Daniil Medvedev wore down Denis Shapovalov 7-5, 7-5 to reach the quarter-finals ahead of his US Open title defense.

Third seed Carlos Alcaraz, a quarter-finalist at Flushing Meadows last year, beat former US Open champion Marin Cilic 7-6(4), 6-1 to set up a meeting with British world number 11 Cameron Norrie, who downed American Ben Shelton 6-0, 6-2.