Last updated: 13th January 2009
Top seed Serena Williams made short work of Sara Errani in the second round of the Sydney International.
Williams, who saved four match points in her first-round win over Samantha Stosur, demolished her Italian opponent 6-1 6-2 in 50 minutes.
"I still think I can improve on some things, and that's what I want to do," said the world number two, who will face Caroline Wozniacki in the quarter-finals.
"I don't want to peak too soon. I just want to stay level for the whole season."
Williams is looking forward to playing eighth seed Wozniacki, who ended the challenge of Britain's Melanie South 6-2 6-0.
"Last I checked she was (world) number 12," added the American. "She's probably even better now.
"It'll be a good match for me going into the Australian Open, and also for her as well."
Second seed Dinara Safina was equally impressive in notching a 6-3 6-0 victory over fellow Russian Vera Dushevina.
Third seed Elena Dementieva, fifth seed Svetlana Kuznetsova and sixth seed Agnieszka Radwanska also reached the last eight.
Dementieva, fresh from victory in Auckland last week, beat Slovakian Jarmila Gajdosova 6-2 6-4, Kuznetsova battled past Estonia's Kaia Kanepi 6-2 2-6 7-6 (7-3) and Radwanska overcame Daniela Hantuchova of Slovakia 6-3 7-5.

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