Serena Williams continued her smooth lead up to next week's Australian Open with a 6-2 6-2 win over Vera Dushevina at the Sydney International on Wednesday.
Playing her second match in 24 hours after a two-month recess, the world number one could hardly have been more dominant as she cruised to victory in just over an hour at the Olympic tennis centre.
Her opponent in Thursday's semi-finals is Frenchwoman Aravane Rezai, who defeated Italian Flavia Pennetta 6-3 6-0.
Victoria Azarenka of Belarus booked her spot in the semi-finals with a 2-6 6-2 7-5 win over Slovakia's Dominika Cibulkova, her third three-setter in as many days.
She will play the winner of Wednesday's last quarter-final between last year's Australian Open runner-up Dinara Safina and her fellow Russian Elena Dementieva, the defending Sydney champion.
Australia's Lleyton Hewitt, chasing his fifth title in Sydney, is the only seeded player through to the last eight of the men's draw after a day of surprise results.
Hewitt sealed his passage in emphatic fashion with a 6-0 6-2 victory over Italian Andreas Seppi to advance to a quarter-final meeting with Marcos Baghdatis of Cyprus.
"It was perfect today," Hewitt said. "If he was gonna win a point, he had to play a bloody good point to get past me."
Baghdatis, the 2006 Australian Open finalist who has struggled with injuries in the last year, upset Serbia sixth seed Viktor Troicki 7-5 6-3
"It's been tough but now I'm back," Baghdatis said.
"I'm in the top 50 and I think I'm hungry and want more and more. That's pretty positive."
The second seed, Czech Tomas Berdych, fell to Australian wildcard Peter Luczak 1-6 6-4 6-2 and the eighth seed Benjamin Becker of Germany lost to France's Richard Gasquet 6-2 7-6.
The third seed, Swiss Stanislas Wawrinka, withdrew before his match against Frenchman Julien Benneteau with a neck problem.
The last time Hewitt played Baghdatis was at the Australian Open two years ago in a titanic match that did not finish until 4.34am, the latest finish in grand slam history.
"I would have wanted to wipe it out of my memory box if I'd lost the match in five sets," Hewitt said.
"But obviously winning an epic match in your home grand slam, yeah, stuff like that always stays in the back of your mind."