Sabine Lisicki suffered a first-round defeat against Timea Babos at the WTA Tour Stuttgart Open, butGerman compatriot Anna-Lena Friedsam progressed on home soil with a straight-sets defeat of Johanna Konta.
Hungarian Babos won 7-6 (7-4) 6-3 on the clay to set up a second-round encounter with world number four Garbine Muguruza.
Lisicki sent down eight aces, but otherwise struggled with her first serve and paid the price as Babos broke three times to the send the world number 50 out at the first hurdle.
Babos maintained the momentum after winning a first-set tie-break, taking a 5-1 advantage before winning her third match point on a disappointing evening for Lisicki in her homeland.
Friedsam, who like Lisicki is hoping to represent her country at the Rio Olympic Games, saw off British number one Johanna Konta in the other first-round match to be played on Monday.
Wildcard entry Friedsam prevailed 6-3 6-3 in the first meeting between the two, breaking twice in each set to ease through.