In other quarterfinal action Friday, third-seed Agnieszka Radwanska of Poland fell to No. 8 Agnes Szavay of Hungary, 6-0, 6-3; Karin Knapp of Italy defeated fourth-seeded Emilie Loit of France, 6-3, 7-6 (8-6); and -- in a battle of unseeded players -- Sara Errani of Italy eliminated Lourdes Dominguez Lino of Spain, 6-2, 6-0.
Saturday's semifinal matches will feature Muller vs. Knapp and Szavay vs. Errani.
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