Top seed Serena Williams advanced to the semi-finals of the Sydney International with a 6-2 6-2 win over Russia's Vera Dushevina.
Dushevina put a forehand wide to give Williams two match points and then double-faulted to finish the match in exactly an hour at the Sydney 2000 Olympics venue.
Williams, playing her only warm-up event ahead of her title defence at the Australian Open, now plays France's Aravane Rezai, who beat Italy's Flavia Pennetta 6-3 6-0
Number two seed Dinara Safina is currently playing Olympic gold medallist Elena Dementieva in another quarter-final -- a rematch from last year's Sydney final.
The winner will meet sixth-seeded Victoria Azarenka, who advanced 2-6 6-2 7-5 against Slovakia's Dominika Cibulkova.
On the men's side, Lleyton Hewitt started his bid for a fifth Sydney title with a 6-0 6-2 win over Italian Andreas Seppi to reach the quarter-finals.
Hewitt won six straight games, then overcame an early service break in the second set, and won six straight games to finish when Seppi double-faulted at match point.
Fourth-seeded Hewitt squared his career head-to-heads at 2-2 with Seppi.
"I've had match points against him and ended up losing -- that scoreline today looks a lot better," Hewitt said.
Hewitt next plays 2006 Australian Open finallist Marcos Baghdatis, who ousted sixth seed Viktor Troicki, of Serbia, 7-5 6-3.
Another Aussie, Peter Luczak, also made the quarters by dumping Czech Republic second seed Tomas Berdych 1-6 6-4 6-2.
Frenchmen Julien Benneteau and Richard Gasquet -- who beat eighth-seeded Benjamin Becker of Germany 6-2 7-6 -- and the USA's Mardy Fish -- a 6-1 6-2 winner over Russia's Evgency Korolev -- also advanced.
US Open champion Juan Martin Del Potro says he's ready to claim his second grand slam in Melbourne this month.
"I feel good with my tennis, I feel confident," Del Potro said.
Meanwhile, injury has forced former Wimbledon finallist David Nalbandian to withdraw from the Australian Open.