The world tennis No.1 Caroline Wozniacki has survived a major scare to move into the Sydney International quarter-finals, recovering from 4-0 down in the deciding set against Dominika Cibulkova.
The Dane looked on the rack in the third set but her Slovakian opponent tensed up considerably as Wozniacki began to find her range, the top seed winning six games in a row to prevail 7-5 2-6 6-4.
She'll face the winner of the Andrea Petkovic-Agnieszka Radwanska match for a spot in the semi-finals.
The defending champion Li Na also had a battle on her hands after losing the first set against South Africa's Chanelle Scheepers.
But after a slow start China's sole grand slam winner dominated the latter stages to take the match 2-6 6-4 6-1.
The world No.5 will now play the winner of the Francesca Schiavone-Daniela Hantuchova match.
In other early action two-time major winner Svetlana Kuznetsova withdrew from her match against Czech Lucie Safarova when down 6-1 2-0, citing heat illness.
Second seed Petra Kvitova is on court next against Romanian Alexandra Dulgheru, the Czech eyeing off the world No.1 ranking if she can win the Sydney tournament here.
That match is followed by Australia's Jelena Dokic and France's Marion Bartoli, with third seed Victoria Azarenka in action later against Jelena Jankovic.