Wickmayer defeated Olga Govortsova 6-3, 6-4, winning 76 percent of the points on serve and facing only one break point in the match. Govortsova, who matched Wickmayer's five aces, took nearly 70 percent of the points on serve herself but Wickmayer was able to convert two of her three break opportunities.
Wickmayer is the lone seeded player to make it to the tournament quarterfinals. Six seeded players, including No. 1 Kimiko Date-Krumm, were ousted in the first round and Dinah Pfizenmaier eliminated seventh-seeded Misaki Doi on Thursday.
Pfizenmaier had 12 aces and won three-quarters of the points on serve in a 6-4, 5-7, 6-0 victory over Doi. She lost one point on serve and 11 points overall in the third set.
Ekaterina Bychkova stopped Valeria Solovyeva 6-4, 7-6 (9-7) in a match sending Russian qualifiers against each other and Luksika Kumkhum came out on top of a 7-6 (7-4), 4-6, 6-3 result against Yaroslava Shvedova in a match that took 2 1/2 hours.
Also advancing Thursday were Petra Martic, who needed only 62 minutes to defeat Anna-Lena Friedsam 6-4, 6-0, and Katarzyna Piter, who was tied 6-6 in the first set with Daria Gavrilova when Gavrilova retired with an injury.