Britain's Johanna Konta was overwhelmed by Czech ninth seed Petra Kvitova in the third round of the Miami Open.
Kvitova did not face a break point against British number one Konta, who won the Miami title in 2017.
She will face fifth seed Elina Svitolina for a place in the quarter-finals after the Ukrainian beat Ekaterina Alexandrova 7-6 (7-1) 6-4.
Victoria Azarenka beat Angelique Kerber 7-5 6-2 to set up a fourth-round meeting with world number one and former doubles partner Ashleigh Barty.
Defending champion Barty, who will retain the top ranking if she reaches the final, beat Jelena Ostapenko 6-3 6-2.