Local favorite Zheng Jie and No. 8-seeded Magdalena Rybarikova posted quarterfinal upsets Thursday at the WTA tournament in China. Zheng topped fourth-seeded Petra Martic 1-6, 6-4, 6-3 before Rybarikova ousted defending champion and No. 2-seeded Jarmila Gajdosova 6-4, 6-3 at the Guangzhou International Women\'s Open. Zheng lost serve just once in the second and third sets while getting all three of her breaks. Martic won more points (83-82) than Zheng in the match due to a large advantage in the first set. Rybarikova had a pair of breaks in each set in beating Gajdosova. She took more points off Gajdosova\'s serve than Gajdosova managed while winning nearly two-thirds of the points on serve. Top-seeded Maria Kirilenko also moved into the tournament semifinals, defeating Tetiana Luzhanska 6-1, 7-5 on the strength of six breaks in nine receiving games. No. 7-seeded Chanelle Scheepers outlasted Urszula Radwanska for a 4-6, 7-6 (8-6), 6-3 victory in a match that took more than three hours. Kirilenko goes against Scheepers and Zheng plays Rybarikova in Friday\'s semifinals.