Venus Williams moved into the semi-finals of the Bank of the West Classic in Stanford with a 6-2 6-2 victory over Maria Sharapova.
Contrasting fortunes for Williams sisters in Stanford
Venus Williams moved into the semi-finals of the Bank of the West Classic in Stanford, California, with a 6-2 6-2 victory over Maria Sharapova.
However, top-seeded sister Serena fell to a surprising 6-2 3-6 6-2 defeat against Samantha Stosur of Australia in the last eight.
Venus had lost all three of her previous hard-court clashes with Sharapova but with the Russian still below her best following last year's shoulder surgery the American was able to capitalise.
Sharapova could hit only 10 winners against 30 errors as Williams took advantage of her struggling serve.
"She's a tremendous athlete and was probably 10 steps faster to the ball than I was," the Russian said.
"I should have taken the opportunities I had. That's something that comes along with playing and right now, it's not on autopilot for me."
Venus will now face third seed Elena Dementieva for a place in the final after the Russian eased past Daniela Hantuchova of Slovakia, 6-2 6-4.
Stosur shines
However, Serena found Stosur in aggressive form as the Aussie booked a semi-final date with eighth-ranked Marion Bartoli.
Stosur's huge serve and heavy groundstrokes proved more than a match for Williams, who had saved four match points when the pair met earlier this year in Sydney.
But on this occasion Stosur held her nerve after Williams had levelled the match, saving two break points in the fourth game of the decider before breaking her opponent to love in the next and never looking back.
"I knew I had my chances in Sydney and I wanted to get in the same position, and this time I got over the line," Stosur said.
"I didn't want a repeat of Sydney so once I got the lead I knew I had to step up and take the pressure to her, which is may be one of the reasons why she double faulted."
Williams added: "She played well and didn't do anything bad. She went for broke and struck all her balls as hard as she could. She never lets you get into a rhythm.
"She had a lot of lucky shots. She's a good framer. But it's obviously all talent. She has mastered that."
Bartoli booked her place in the last four with a surprise victory over fourth seeded Jelena Jankovic of Serbia, 3-6 7-6 6-3.
