Wozniacki, who is the tournament's No. 1 seed, was down two breaks early but charged back for a 7-6 (7-4), 6-2 victory over Urszula Radwanska. Wozniacki ended up with five breaks over Radwanska's 10 serving games.
Second-seeded Angelique Kerber needed three sets to get past Stephanie Foretz Gacon, countering seven dropped service games with nine breaks as neither player won half of the points on serve.
No. 4-seeded Monica Niculescu breezed past Valeria Savinykh 6-2, 6-2 while fifth-seeded Kaia Kanepi topped Anastasia Rodionova 6-3, 6-4 and Mona Barthel, the sixth seed, beat Johanna Larsson 6-3, 6-4 in other matches in which the seeded player advanced.
Qualifier Johanna Konta was sent to the second round when, after Konta built a 6-3, 1-0 lead, seventh-seeded Ksenia Pervak retired.
Alize Cornet lost just 15 points in a 6-0, 6-0 whitewash of Malou Ejdesgaard. The match took only 43 minutes.
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