Sixth seed Alison Riske has progressed to the WTA Tianjin Open semi-finals, while home favourite Saisai Zheng is also through.
US player Riske overcame compatriot Varvara Lepchenko, the fourth seed, 7-6 (7/5) 6-3.
Unseeded Chinese ace Zheng had to battle to beat Romania’s Sorana Cirstea 6-4 2-6 6-1.
Third seed Belinda Bencic, of Switzerland, is also through, triumphing 6-4 4-6 6-2 against Taiwan’s Hsieh Su-Wei.