Ukraine's Sergiy Stakhovsky moved into the second round of the German Open in Hamburg with a 64-minute, 6-2 6-3 victory over Argentina's Maximo Gonzalez.
Stakhovsky was joined in round two by Finland's Jarkko Nieminen, who beat Colombia's Santiago Giraldo 6-4 6-3, and Argentina's Carlos Berlocq, who ousted Dutchman Robin Haase 6-2 6-2.
Home wild-cards Julian Reister and Tobias Kamke were popular winners over Denis Istomin and Pere Riba respectively, while another German, qualifier Bastian Knittel, beat Ivan Dodig 6-4 6-3.
Other successful qualifiers were Spain's Albert Ramos, who beat Adrian Mannarino, and Romanian Victor Crivoi, a straight-sets winner over Guillermo Olaso. Czech lucky loser Lukas Rosol also advanced.