Hercog defeated Julie Coin 6-0, 6-2 in one of three second-round matches played Wednesday. Hercog also won in straight sets on Tuesday against No. 1 seed Kirsten Flipkens.
Christina McHale will meet Hercog in the quarterfinals after pulling off a mild upset of eighth-seeded Caroline Garcia 2-6, 7-6 (9-7), 6-3.
Sixth-seeded Marina Erakovic also earned a quarterfinal berth with a 6-2, 6-1 decision over Barbora Zahlavova Strycova.
The first round was completed with No. 5 seed Eugenie Bouchard defeating Sofia Arvidsson 6-1, 2-6, 7-6 (7-0); Petra Martic winning over Lucie Hradecka 6-4, 7-6 (7-1) and Andrea Hlavackova outlasting Anastasia Rodionova 7-6 (7-3) 5-7, 6-1.
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