Last year's finalist Iga Swiatek eased past Romanian Sorana Cirstea 6-1, 6-1 to book a fourth-round meeting with home favourite Sara Sorribes Tormo or ex-world No 1 Victoria Azarenka on Saturday.
Play started with the roof closed due to wet conditions but that had no effect on Swiatek, who leapt to a 4-0 lead inside 22 minutes.
The top seed got broken while serving for the opening set at 5-0 but that only delayed the inevitable as she struck right back to close out the set on the 40-minute mark.
The second set followed a similar pattern and Swiatek wrapped up the victory with a service winner, losing just two games in the one-hour 17-minute clash.
"For sure the weather is different than last year but still I know how to play in these kind of conditions. I feel really comfortable," said Swiatek, who is seeking a third WTA 1000 crown of the season this week.