Hertogenbosch - Leading seed Fernando Verdasco of Spain has survived a shaky performance to beat Paul-Henri Mathieu of France 2-6, 6-4, 6-4 and open his account in the Topshelf Open on Tuesday.
Verdasco, the highest seeded man after countryman David Ferrer pulled out, served up 13 aces but also 15 double faults.
He improved to 6-0 against Mathieu.
Top-seeded woman Simona Halep, the French Open runner-up, opens against Belarus qualifier Olga Govortsova.
Results from the third day of the 's-Hertogenbosch ATP/WTA Open on Tuesday (x denotes seed):
Men's singles
First round
Fernando Verdasco (ESP x2) bt Paul-Henri Mathieu (FRA) 2-6, 6-4, 6-4
Roberto Bautista Agut (ESP x3) bt Daniel Gimeno (ESP) 6-1, 6-3
Juergen Melzer (AUT x8) bt Alejandro Falla (COL) 6-4, 6-3
Jan-Lennard Struff (GER) bt Lukas Rosol (CZE) 6-4, 6-2
Mate Pavic (CRO) bt Alejandro Gonzalez (COL) 7-6 (7/4), 6-3
Joao Sousa (POR) bt Paolo Lorenzi (ITA) 6-3, 3-6, 6-3
Nicolas Mahut (FRA) bt Kimmer Coppejans (BEL) 6-3, 3-6, 6-3
Women's singles
Second round
Garbine Muguruza (ESP x7) bt Yvonne Meusburger (AUT) 6-4, 6-1
Magdalena Rybarikova (SVK) bt Andrea Petkovic (GER x5) 6-4, 6-7 (4/7), 7-5
First round
Simona Halep (ROM x1) bt Olga Govortsova (BLR) 7-5, 6-2
Vania King (USA) bt Eugenie Bouchard (CAN x3) 2-6, 6-3, 6-3
Carla Suarez Navarro (ESP x4) bt Barbora Zahlavova Strycova (CZE) 6-4, 6-2
Yaroslava Shvedova (KAZ) bt Dominika Cibulkova (SVK x2) 6-2, 3-6, 6-3