Errani needed only 67 minutes to dispose of Cadantu 6-2, 6-2. She is looking for her second title at this tournament.
Irina-Camelia Begu will try to upset Errani in the semifinals after rallying past qualifier Estrella Cabeza Candela 5-7, 6-4, 6-4.
The other semifinal will send Laura Robson against Barbora Zahlavova Strycova.
Strycova won over third-seeded Julia Goerges 7-6 (7-4), 6-7 (4-7), 6-1.
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