Top seed Justine Henin-Hardenne continued to steamroll her way through the Pacific Life Open draw, taking apart 17th seeded Argentine Gisela Dulko 6-3, 6-2 in a one-sided quarter-final match on Thursday.
The Belgian will a face fourth seed Elena Dementieva, who overcame a terrible start before ousting Serbian teenager Ana Ivanovic 2-6, 6-4, 6-2 to reach the last four.
In the men's draw, two-time champion Roger Federer strolled into the semi-finals with a 6-2, 6-3 win over sixth seed Ivan Ljubicic.
Federer will face a resurgent Paradorn Srichaphan of Thailand, who downed Finland's Jarkko Nieminen 7-6, 3-6, 7-5 in two hours and 41 minutes to reach his first Masters Series semi-final since 2003.
Former world number one Henin-Hardenne, who has yet to drop a set in four matches, had few problems with the speedy Dulko, who she had never played before.
The Argentine tried to wear her opponent down by counter attacking, but the Belgian had far too much power and a few too many tricks up her sleeve.
"When you never played someone, you don't know really what to expect," Henin-Hardenne said.
"I know she had nothing to lose, so I knew it was going to be a tough match. But I think I controlled the match, even if my attitude was a bit negative sometimes."
SIXTH WIN
Federer suffocated Ljubicic from the outset to record his sixth straight win over the Croatian.
The Swiss had little trouble in frustrating Ljubicic with his sublime placements of the ball.
"I consider myself a top-five player but that doesn't mean I'm close to Roger," world number six Ljubicic said.
"He's much better than me and anybody else except maybe Rafael Nadal, and he only gives him trouble because he's a lefty. "But when he's on top of his game, no one can give him any trouble."
Federer will face Paradorn for a place in the final.
The 18-year-old Ivanovic ran Dementieva ragged in the first set but the Russian's greater experience allowed her to turn things around in the final two sets.
Dementieva drew Ivanovic into lengthy rallies and coaxed errors out of her opponent.
"I'm a very slow starter," Dementieva said. "I usually start to play better when I am in trouble and that's what happened today."
On Friday, second seed Nadal will face 25th seed Marcos Baghdatis of Cyprus in the quarter-finals, while 12th seed James Blake of the U.S. will play 24th seed Igor Andreev of Russia.
Comeback queen Martina Hingis will go up against third seed Maria Sharapova of Russia in the other women's semi-final.