Third seed and two-time Grand Slam winner Svetlana Kuznetsova of Russia has earned a place in the semi finals of the ASB tennis classic in Auckland.
Kuznetsova won in two sets, 6-4, 6-3, in her Thursday evening match against Sara Errani of Italy.
The other semi-finalists from Thursday's quarter-final round are Angelique Kerber of Germany, fourth seed Flavia Pannetta of Italy and China's Zheng Jie.
Top seed Sabine Lisicki of Germany was forced to retire injured in her quarter-final against Kerber.
Kerber won the first set 6-4 and was up 4-3 in the second when Lisicki withdrew with an abdominal injury.
Pennetta beat Elena Vesnina of Russia in straight sets, 6-2, 6-1 while Jie had little trouble in beating Lucie Hradecka of the Czech Republic, winning 6-2, 6-3.
Kuznetsova will meet Jie in the semi-final on Friday while Kerber will play Pennetta.