Britain's Anne Keothavong beat Mandy Minella to reach the second round of the Luxembourg Open, but her compatriot Elena Baltacha was knocked out.
Keothavong, who had to come through three qualifying matches to make the main draw, overcame Luxembourg's world number 122, 6-3 1-6 6-3.
The Londoner, 28, battled through despite serving seven double faults and having to save eight break points.
Baltacha, the world number 58, lost 7-5 6-1 to German sixth seed Julia Goerges.
The Scot broke in the first game of the match and looked on course to take the set until Goerges stormed back with successive breaks.
Goerges, ranked 21, served five aces and broke her opponent twice in a one-sided second set.
Keothavong's win followed an impressive performance in the Generali Ladies event in Austria last week, where she reached the second round and took third seed Jelena Jankovic to three sets.
"I went on a walk about in the middle of my match this evening but eventually found my way," she said on Twitter after her match. "Want to sleep but adrenaline still high."
Keothavong will play fifth seed Ana Ivanovic - coached by Briton Nigel Sears - on Thursday after the Serbian defeated France's Virginie Razzano 7-6 (7-2) 6-4.