{blackbabes} Williams, Azarenka advance to semis at Madrid

MADRID, Spain -- Serena Williams brushed aside Maria Sharapova 6-1, 6-3 to advance to the Madrid Open semifinals along with top-ranked Victoria Azarenka on Friday.

Williams sealed her seventh straight win over Sharapova with an emphatic slam on the new blue-clay court.

Earlier in the Spanish capital, Azarenka overcame a shaky start to beat French Open winner Li Na 3-6, 6-3, 6-3.

Williams opened strong, hitting six aces and earning two early breaks to take the first set against the second-ranked Russian.

Sharapova finally showed some fight and broke for love to even the score at 2-2 in the second set, but she quickly squandered her break with a costly sixth double fault to fall behind for good.

Williams, who improved to 11-0 on clay this year, will face either U.S. Open champion Sam Stosur or Czech Lucie Hradecka.

After Azarenka struggled on serve early on, last year's runner-up found her stride and broke her Chinese opponent's first two service games of the second set en route to pulling even at a set each.

Azarenka, who has won four titles this season, then used her powerful groundstrokes to jump out to an insurmountable 4-0 lead in the decider before holding off Li's late charge.

The Belarusian will face the winner of the quarterfinal between Agnieszka Radwanska and Varvara Lepchenko.

On the men's side, Argentina's Juan Martin del Potro hit 10 aces to beat Alexandr Dolgopolov of Ukraine 6-3, 6-4 to reach the semifinal with Tomas Berdych.

The six-seeded Berdych defeated Fernando Verdasco 6-1, 6-2. The Spaniard made 24 unforced errors and showed little of the flare on display Thursday when he ousted Rafael Nadal.

Defending champion Novak Djokovic will face Janko Tipsarevic of Serbia and Roger Federer will play David Ferrer later on Friday.