Angelique Kerber advanced to the semifinals Thursday over top-seeded Sabine Lisicki at the ASB Classic tennis tournament in New Zealand. Kerber, who has never lost to Lisicki, was ahead 6-4, 4-3 Thursday when Lisicki complained of a back injury and retired. Kerber had four breaks in eight receiving games and won 56 percent of the points both serving and receiving. She\'ll next go against fourth-seeded Flavia Pennetta, who defeated Elena Vesnina 6-2, 6-1 with six breaks in eight games. Pennetta took 61 percent of the points in the match. The other semifinal pairs No. 3-seeded Svetlana Kuznetsova against Zheng Jie. Kuznetsova had eight aces and no double faults in a 6-4, 6-3 victory over Sara Errani. Zheng didn\'t face a break point in a 6-2, 6-3 win over Lucie Hradecka. She dropped 10 points over nine service games. Kerber and Pennetta have split their two previous meetings while Kuznetsova is 6-0 against Zheng. Friday\'s semifinals winners will play Saturday for the tournament title and $37,000. The runner-up will take home $19,000 and the other semifinalists will each earn $10,200.