By Matt Cronin

STANFORD, California (Reuters) - Serena Williams has still not kicked post Wimbledon jet lag, but she still managed to beat Chanelle Scheepers 6-4 6-0 in the quarter-finals of the Stanford Classic on Friday.

Second seed Mario Bartoli and third seed Dominika Cibulkova, however, did not fare as well with France's Bartoli beaten by Yanina Wickmayer 6-3 6-2, while Romania's Sorana Cirstea beat Slovakia's Cibulkova 6-7 6-2 6-0.

Williams, who won her fifth Wimbledon singles title last week, arrived in Northern California on Monday and had been unable to get a good's night sleep.

She woke up at 1 a.m. (0800 GMT) on Friday and stayed awake for five hours watching the final season of the television show Desperate Housewives.

"I was hoping to fall back asleep but I didn't," Williams said. "I was crying as always. I love that show. I was wide wake as if I was in Europe still."

In her victory over the South African, Williams felt sluggish but she woke up toward the end of the first set.

"I didn't feel great going out, but I expected to stay consistent till I started to feel better and then I started moving well and that really helped a lot," Williams said.

Wickmayer went into her match against Bartoli with an 0-3 record but out hit the world number 10 from inside the baseline to reach her second semi-final of the year.

"I tried not to give her too many angles and really wanted to go for my shots only when I had the chance," the fifth-seeded Belgian said.

"In our other matches, I think she really just beat me at my own game. Today, I think I was playing smarter." Continued...