's-Hertogenbosch, The Netherlands (Sports Network) - Dutch wild card Igor Sijsling and Gilles Muller of Luxembourg were Sunday's first-round winners at the $500,000 UNICEF Open, a final grass-court Wimbledon tune-up.

Sijsling took down sixth-seeded Jarkko Nieminen of Finland 6-2, 6-4 at Autotron Rosmalen.

Muller outlasted fifth-seeded Colombian Santiago Giraldo 7-6 (7-5), 6-7 (4-7), 6-3.

Dmitry Tursunov beat Croat Ivan Dodig in last year's finale.

The newest champion here will collect $85,000.