Serena Williams pulls out of WTA tournament

(CNN) -- Second seed Serena Williams withdrew from the WTA event at the Home
Depot Center in Carson City as she gave up the fight against a left knee
injury.

Serena is battling to be fit for the Beijing Olympics and the U.S. Open.

Serena, beaten by her sister Venus in the Wimbledon final, had withdrawn
from last week's tournament at Stanford, but was determined to press on
against the advice of medical personnel and her father.

But after warming up on Tuesday morning, she accepted the inevitable and
joined sister Venus, Lindsay Davenport and Svetlana Kuznetsova on the injury
sidelines.

She was scheduled to open on Wednesday against Petra Kvitova of the Czech
Republic.

"I've been getting intensive therapy and doing everything in my power to get
my knee in shape for this week, waiting until the last possible moment to see
if I could play," Williams said in a statement.

"Unfortunately after hitting this morning, I knew that I wasn't going to be
ready for this week. In the meantime, I'm working hard to be ready for the
Olympics and U.S. Open."

In opening round action, sixth seed Daniela Hantuchova, the runner-up in the
East West Bank Classic three years ago, made an unexpectedly early exit on
Tuesday night, losing to Olga Govortsova, 6-2 6-4.

Govortsova, 19, of Belarus, squandered three match points on her serve in the
ninth game of the second set, then capitalized on the fourth one with a
forehand to the open court at 30-40 on Hantuchova's serve.

Hantuchova, who still is trying to find her form after a long layoff from a
stress fracture in her right heel, said that her game is "not there yet. I
just have to be patient, keep practicing and keep working hard. It's a long
way back," she told the Associated Press.

Anna Chakvetadze, of Russia, the third seed, had no trouble in her
second-round match, toppling Marta Domachowska of Poland, 6-1 6-1, in 49
minutes.

Top seed Jelena Jankovic, who could claim the world number one ranking in the
world by winning the tournament, will play her first match on Wednesday
against 98th-ranked American Vania King.

Jankovic is coming back from a knee injury and has been idle since Wimbledon.