Kim Clijsters stormed into the semi-finals of the Sydney International with a straight sets demoliton of Victoria Azarenka on Wednesday.
The Belgian world number three reaffirmed her status as favourite for next week's Australian Open with five service breaks on the way to a 6-3, 6-2 win over the seventh-seeded Azarenka in 85 minutes.
She will face the winner of unseeded pair, Dominika Cibulkova of Slovakia and Russia's Alisa Kleybanova in Thursday's semi-finals.
China's Li Na will take on Serbian qualifier Bojana Jovanovski in the other semi, after Jovanovski beat Flavia Pennetta 6-4, 6-1 in their quarter-final.
With no Serena Williams in Melbourne and the patchy early season form of the two top-ranked women, Caroline Wozniacki and Vera Zvonareva, Clijsters was in devastating form.
Li was the first player into the semi-finals after a gruelling dogfight with Russia's Svetlana Kuznetsova.
The 11th-ranked Li wore down the two-time Grand Slam champion, 3-6, 7-6 (7/4), 6-3.
Del Potro's comeback hits the skids
Sydney: Former U.S. Open champion Juan Martin Del Potro's comeback from injury faltered on Wednesday when his lack of match practice was exposed at the Sydney International.
The 22-year-old Argentine declared himself free of pain when he won his first match in a year in three sets on Monday but he was well beaten 6-2 7-5 by Germany's Florian Mayer in the second round at the Sydney Olympic Park.
"Everything is tough after long, long time," Del Potro said. He added, "But if I'm here it's because I want to play. I want to try again.”