Second seed Dominika Cibulkova is through to the quarter-finals at the Bank of the West Classic after defeating Urszula Radwanska 7-6 (3), 6-3.
Cibulkova has been in fantastic form as of late as she won the Aegon International before reaching the quarter-finals at Wimbledon.
The 27-year-old will face Japan’s Misaki Doi in the quarter-finals after the fifth seed downed compatriot Nao Hibino 6-3, 6-4.
Fourth seed Coco Vandeweghe battled past Nicole Gibbs 2-6, 6-4, 6-2, while American wildcard Catherine Bellis continued her excellent run in the tournament as she took down Sachia Vickery 4-6, 6-4, 6-3.
Alison Riske also booked her spot in the last eight after beating Romanian qualifier Ana Bogdan 3-6, 6-2, 6-4.