US Open champion Kim Clijsters suffered a second-round defeat to Patty Schnyder at the BGL Luxembourg Open.
The Belgian former world number one, who made a memorable return from retirement with victory at the US Open last month, lost 6-4 3-6 7-6 (8/6) to the Swiss player as her serve failed to fire.
Clijsters had 11 double faults in the defeat as Schnyder moved through to a clash with Sabine Lisicki of Germany.
Fourth seed Daniela Hantuchova earlier came thr! ough a tough clash with Lucie Hradecka.
The Slovakian edged her Czech opponent 7-5 3-6 6-2 to book her place in the next stage and was joined by fifth seed Yanina Wickmayer.
The Belgian saw off Alize Cornet 7-5 7-6 (8/6), while eighth seed Shahar Peer beat Spain's Carla Suarez Navarro 3-6 6-3 6-1.
Katarina Srebotnik lost the first set against Anne Kremer but rallied to win the next two at a cost of just two games for a 2-6 6-4 6-0 victory.
