Gallovits-Hall posted a 7-6 (7-3), 3-6, 6-2 decision over the 2010 titleholder in the clay-court event and will take on Lara Arruabarrena-Vecino in Saturday's semifinals.
Arruabarrena-Vecino breezed past qualifier Paula Ormaechea in their quarterfinal contest.
The other semifinal will send Timea Babos against Alexandra Panova. Babos was a 6-4, 6-4 winner over Yaroslava Shvedova and Panova ousted Karin Knapp 6-4, 6-4.
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