The Romanian, who notched her first career victory last week in Nuremberg, Germany, stayed hot by routing the Italian defending champ 6-0, 6-1 at Autotron Rosmalen in the Netherlands.
Others seeds, however, fared better Wednesday.
Meanwhile, fourth-seeded Kirsten Flipkens of Belgium overcame Dutch wild card Michaella Krajicek 7-6 (8-6), 7-6 (7-3).
Spanish qualifier Garbine Muguruza also moved on to the quarterfinals with a victory.
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