Belgium\'s Kim Clijsters cruised into the semi-finals of the Brisbane International with a comfortable 6-3, 6-2 win over Czech player Iveta Benesova on Thursday. Fifth seed Clijsters took 78 minutes to see off Benesova, who had beaten top seed Samantha Stosur in the previous round. Benesova struck the ball beautifully at times but she was unable to reproduce the consistency she showed against Stosur to bother the four-time Grand Slam champion. \"I think I was looking for the lines a little bit better and... I tried to get in charge of the rallies as soon as I could because I knew that once she gets behind the ball and gets a good look at it she\'s so sharp,\" Clijsters said. \"I\'m starting to feel more confident, the little ups and downs that happened in my previous matches weren\'t there, which is good, which is why I\'m here, to get those matches and improve every match and to learn from the things that weren\'t going well.\" Clijsters will now play Daniela Hantuchova in the semi-finals after the Slovakian was handed a place in the last four when Serena Williams withdrew on Wednesday night with an ankle injury. Estonia\'s Kaia Kanepi caused the tournament\'s second upset in as many days when she dumped second seed and 2011 runner-up Andrea Petkovic from the tournament 6-1, 7-6 (9/7). Kanepi raced through the first set against a woeful Petkovic before the German at last began to find some form to fight hard through the second. The powerful Estonian had five match points before finally sealing the win with a forehand volley to the open court. \"I just played really bad in the first set,\" Petkovic said. \"I also made a lot of unforced errors and I think that was the difference today.\" Third seed Francesca Schiavone demonstrated her remarkable stamina as she saved two match points on her way to a 5-7, 7-6 (7/2), 6-3 win over Serbia\'s Jelena Jankovic. The two women were on court for almost three hours as they battled each other to a standstill, the Italian clinching it on her third match point. Jankovic, who had match points at 6-5 in the second set, trudged off court a disconsolate figure as a delighted Schiavone saluted the big crowd in the Pat Rafter Arena. Schiavone was involved in the longest women\'s match in Grand Slam history at the 2011 Australian Open, when she beat Svetlana Kuznetsova in four hours, 44 minutes. She said later her ability to close out long matches had as much to do with her mental toughness as her physical fitness. \"The body can\'t go without the mind and the opposite,\" she stressed. \"Maybe sometimes you have to do a little bit more running, but the next point might need more thinking.\" Schiavone had a novel approach to recovering from such a long match in time for her semi-final just 24 hours later. \"A massage for sure... then I should eat a cow,\" she said with a laugh.