BRISBANE (Australia) (AFP) Star Belgian duo Kim Clijsters and Justine Henin were both forced to three sets before winning their quarter-finals at the Brisbane International on Thursday. Clijsters beat Czech Lucie Safarova 6-1, 0-6, 6-4 while earlier in the day Henin outlasted seventh seeded Hungarian Melinda Czink 6-2, 3-6, 7-6 (7/5). Top seed Clijsters now faces German surprise packet Andrea Petkovic for a place in Saturdays final and Henin plays third seed Ana Ivanovic of Serbia. Clijsters needed four match points to finally see off Safarova, who looked all at sea as she surrendered the first set in just 23 minutes. But the Czech came out with all guns blazing in the second, blasting winners from all over the court and forcing Clijsters into a host of errors, taking the set in three minutes less than she lost the first. In an intriguing third set, Clijsters broke in the fifth game and held on for the win. I felt like in the second set even before I had the chance to work my way into the rally, shed already hit a winner most of the time, Clijsters said. Thinking back on it now, maybe I should have taken a little more risks at times, but I think the difference for her in the first set to the way she played in the second was so big it kind of surprised me at the time. Henins match followed a similar pattern to Clijsters as she won the first set comfortably, lost the second then fought off a tenacious Czink to claim the third. Henin needed six match points and a shade over two hours, 20 minutes to book her place in the final four. I love these kinds of situations, especially after, not during the match, she said. Henin said she had recovered well from playing three matches in a row. I feel better today, much better (than yesterday), Henin said. It was a long match and mentally it was very difficult but physically I feel much better. I am an old woman of 27, she joked. I came here to play matches and thats what I have done, so no complaints. Ivanovic survived her own second set meltdown to squeeze past Russian Anastasia Pavlyuchenkova 6-2, 7-6 (8-6). The third seed looked set to wrap up the quarter-final in under an hour when she led 4-0 in the second set only for Pavlyuchenkova to come storming back. The Russian had a set point in the tie-break but couldnt take advantage and a relieved Ivanovic was able to close the match out in two. Ivanovic said she was confident ahead of her clash with Henin. Shes playing really good and she seems to be in good shape so its going to be a good test for me. Whatever happens Im just going to try and enjoy it, the Serb said. Unseeded German Andrea Petkovic stunned fourth seed Daniela Hantuchova in straight games 6-4, 6-2. Petkovic, who beat eighth seed Iveta Benesova in the first round, broke her Slovak opponent three times to reach the semi-finals. The political science student was refreshingly honest about playing Clijsters. Kim is known for her strengths and not too many weaknesses, but Ill try to find some, the 22-year-old said. Im not scared, I will just try to play my game and well see what happens if she kills me she kills me, if not, well see.