Cibulkova, Suarez Navarro advance in Den Bosch

A pair of top-three seeds, Dominika Cibulkova and Carla Suarez Navarro, posted first-round wins Monday at the $235,000 Topshelf Open, a final grass-court Wimbledon tune-up.

The second-seeded Slovakian Cibulkova barely snuck past Spaniard Lourdes Dominguez Lino 6-1, 6-7 (5-7), 7-6 (7-3), while the third-seeded Suarez Navarro, of Spain, drubbed Swede Johanna Larsson 6-3, 6-2 at Autotron Rosmalen.

Two other seeds suffered upsets on Day 2, as Spanish qualifier Garbine Muguruza took out No. 6 Mona Barthel of Germany 7-5, 1-6, 6-2 and Bulgarian grass-court specialist Tsvetana Pironkova toppled No. 8 Kristina Mladenovic of France 6-4, 6-4.

Several other women notched opening-round victories, including American Lauren Davis and last week's Nuremberg, Germany titlist Simona Halep. Davis downed Czech qualifier Andrea Hlavackova 6-3, 6-4, while the Romanian Halep held off German Annika Beck 6-1, 2-6, 6-3.

On Tuesday, top seed Roberta Vinci of Italy will open her stay in Den Bosch against Estonian Kaia Kanepi. Vinci titled here two years ago.