Third-seeded Kaia Kanepi of Estonia dropped her first set but came back to eliminate Nicole Vaidisova, a Czech wild card, 4-6, 6-1, 6-3.
Czech Petra Kvitova, the fifth seed, topped Dutchwoman Michaella Krajicek 6-4, 7-5.
The No. 7 seed, American Vania King, fell to Arvidsson, a qualifier in this year's tournament. Arvidsson scored a 3-6, 6-4, 6-2 comeback victory.
Anne Keothavong of Britain and Karolina Sprem of Croatia also advanced Wednesday.
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