Donna Vekic bowed out of the Linz Open after a 6-1 6-1 humbling at the hands of Timea Babos on Tuesday.
Eighth seed Vekic has recorded wins over Sloane Stephens and Caroline Garcia since falling at the first hurdle at the US Open, but she was no match for Babos in a one-sided contest that lasted 67 minutes.
The Croatian's surprising loss clears a path for top seed Julia Goerges - in action on Wednesday - to reach the last four.
Camila Giorgi, the only other seed involved on Tuesday, was tested by Pauline Parmentier before eventually emerging a 6-3 7-6 (7-4) winner.
The Italian will next meet qualifier Jil Teichmann, who beat Sorana Cirstea 6-4 6-2. Lucky loser Kristyna Pliskova also made the last 16, defeating Valentini Grammatikopoulou in straight sets.