Clijsters, the 2005 U.S. Open titlist and the runner-up at the Aussie Open in 2004, earned a 6-3, 2-6, 6-4 victory over Hingis.
Clijsters' semifinal opponent Thursday will be third-seeded Frenchwoman Amelie Mauresmo, who routed seventh-seed Patty Schnyder of Switzerland, 6-3, 6-0, in just 52 minutes Wednesday at Rod Laver Arena.
The other semifinal Thursday will pit Henin-Hardenne against fourth-seeded Russian Maria Sharapova.
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