The top-seeded Hingis gained an easy route to the semifinals when Domique Van Roost of Belgium was forced to retire with what was believed to be a hamstring injury. Van Roost lost the first set to her Swiss opponent, 6-1, before withdrawing.

In a matchup of the only two Frenchwomen left in the tournament, the sixth-seeded Mauresmo ousted No. 3 Mary Pierce, 6-2, 6-3.

Hingis has won five of her six lifetime meetings with Mauresmo, including a celebrated victory in the finals of last year's Australian Open. In a radio interview at the time, Hingis was critical of Mauresmo's openly gay lifestyle and muscular physique.

"We've got over that now. We're all one big, happy family," Hingis said.

Second seed and defending champion Lindsay Davenport of the United States also advanced to the semifinals with a hard-fought 6-7 (5-7), 6-3, 6-4 win over Arantxa Sanchez-Vicario of Spain.

With the third set tied 4-4, Davenport used a thunderous forehand to overcome 15-40 hole and regain her hold on the match.

"With longer rallies and hitting a lot of balls, it was a great match for me to play before Melbourne," Davenport said.

Davenport advances to face eighth seed Anna Kournikova of Russia, who needed three sets to eliminate American Alexandra Stevenson, 4-6, 6-2, 6-2.

Kournikova posted an impressive win over American Jennifer Capriati, the 1993 champion and 1997 runner-up, on Wednesday and kept alive her bid to capture her first WTA Tour title.

Kournikova and Davenport have split four lifetime meetings.

On the men's side, lucky loser Ivan Ljubicic of Croatia continued his improbable run with a 6-3, 3-6, 7-5 win over fifth seed Karol Kucera of Slovakia. A lucky loser is a player that loses in the qualifying bracket but makes the main draw after withdrawals.

Ljubicic, who got a spot when Fabrice Santoro of France pulled out with a shoulder injury, blew away third seed and defending champion Todd Martin of the United States on Wednesday.

"I am very tired and I am going to give everything to recover," Ljubicic said. "I will just try to keep going."

Next up for Ljubicic, who at age 12 was forced to flee his homeland of Bosnia due to ethnic tensions, is Australian Jason Stoltenberg, who took care of second-seeded Ecuadorian Nicolas Lapentti, 4-6, 7-5, 6-1.

Lapentti was the only seeded player left in the men's draw.

Australian teenager Lleyton Hewitt extended his season-opening winning streak to eight matches with a 6-3, 6-4 victory over Adrian Voinea of Romania.

Hewitt won his hometown tournament in Adelaide last week for the second time in three years.

"I've said the whole time my goal is to be hitting the ball well going into the Australian Open," Hewitt said.

Hewitt will face Alex Corretja of Spain, last year's runner-up, who defeated Slava Dosedel of the Czech Republic, 3-6, 7-5, 6-3.

First prize for the men is $46,000, while the women's champion pockets $75,000.