- Caroline Wozniacki beats Ana Ivanovic 6-3 7-5 in Dubai Open quarterfinals
- Both players have been former world number one ranked
- Agnieszka Radwanska thrashes Sabine Lisicki in their quarterfinal
- Jelena Jankovic beats Sam Stosur to reach the semifinals
Caroline Wozniacki beat Ana Ivanovic in a battle of former world number one ranked players to reach the semifinals of the $2 million WTA tournament in Dubai Thursday.
The Dane, who lost the top spot during the Australian Open earlier this year, won an entertaining encounter 6-3 7-5 in one hour 33 minutes.
Former French Open champion Ivanovic threatened a comeback when she twice retrieved deficits in a thrilling second set, but Wozniacki achieved her sixth break of service to lead 6-5 and serve for the match.
Ivanovic saved one match point but hit a return long on the second to leave defending champion Wozniacki on course to defend her title.
Her semifinal will be against Julia Goerges, the improving German, who beat Slovakian star Daniela Hantuchova 4-6 6-3 6-4 in their last eight match
The unseeded Goerges has beaten Wozniacki the last two times they have met, both on clay.
Wozniacki is the highest ranked player left in the tournament after the withdrawals of Victoria Azarenka and Petra Kvitova through injury.
Earlier, Agnieszka Radwanska of Poland reached her second semifinal in two weeks by thrashing German Sabine Lisicki 6-2 6-1.
The fifth seed will play in-form Jelena Jankovic in their last four clash Friday.
Jankovic, also a former world number one, upset fourth seed and reigning U.S. Open champion Samantha Stosur 6-4 6-2 to reach her fifth Dubai semifinal since 2005.