Defending champion Sorana Cirstea advanced to the semifinals at the clay-court Istanbul Championship by defeating Julia Grabher of Austria 7-5, 6-1 on Friday.
The Romanian last year ended a 13-year wait for her second career singles title when she upset Elise Mertens in the final.
Cirstea will next play third-seeded Veronika Kudermetova, who outlasted Anna Bondar 7-6 (9), 7-6 (3).
Also, Yulia Putintseva of Kazakhstan reached the last four after coming back to beat sixth-seeded Ajla Tomljanovic of Australia 5-7, 6-2, 6-4.
The 51st-ranked Putintseva will next face Russian player Anastasia Potapova, who advanced by defeating seventh-seeded Sara Sorribes Tormo of Spain 6-2, 6-2.