Venus bogged down in Paris clay pit

The Williams sisters can give the impression that they believe they are taking on the whole world. Here at the French Open they may get no further than Serbia.

The draw has produced a bottom half in which Serena and Venus are seeded to meet Ana Ivanovic and Jelena Jankovic respectively in the quarter-finals. Serena and Ivanovic were emphatic straight-sets winners on the first day, but Venus and Jankovic made less convincing progress on the second.

Venus has never enjoyed the same success on clay as on faster surfaces – she was beaten by her sister in her only final here six years ago – and was made to struggle yesterday by the oldest player in the women's singles. Tzipora Obziler, a 35-year-old Israeli who has never gone beyond the second round of a Grand Slam tournament, went a break up in the final set before losing 6-3, 4-6, 6-2.

Williams broke Obziler's serve in the fifth and ninth games to take the first set, but from 4-1 up in the second the Wimbledon champion lost six games in succession. Obziler, however, was unable to drive home her advantage and dropped her next four serves to give Williams victory. The American's tally of 41 winners and 37 unforced errors told their own story of her erratic play.

"Sometimes tennis isn't always won as quickly as you want," Williams said. "I think she really played some good tennis. She made some good shots and fought really hard for that second set. It was just important to close it out in the third."

Jankovic won the first three games against Romania's Monica Niculescu but needed a stroke of luck on her way to a 7-6, 6-2 victory. Leading 4-2 in the tie-break, the Serb saw her drop volley roll along the top of the net before falling on to the other side of the court. Jankovic won the tie-break 7-3 and played with more confidence in the second set.

Playing at Roland Garros can be a trial for the home players and Emilie Loit has grown tired of the pressure. The 28-year-old, making her 11th appearance here, revealed after her 1-6, 6-4, 8-6 victory over China's Zi Yan: "I was sick and tired of tennis three weeks ago. I simply couldn't take it any more. I put my racket away and just went jogging. I played a few rallies with friends, like anybody else playing in a club, but my preparation was really easy. I decided to come here with no pressure." A case of being a Loit unto herself?

Harkleroad reveals her naked ambition

Ashley Harkleroad may have lost in straight sets to Serena Williams at Roland Garros, 6-2, 6-1, but she will shortly gain a distinction unique among her fellow professionals when she takes her clothes off for the August edition of Playboy.

The American received the offer during a recent injury lay-off.

"I thought, well, I'm not really doing anything right now so I thought about it and it was something that I did," she said. "I'm proud of my body. It was hard work, but it was just a completely different experience. It was fun.

"I'm just trying to represent a female athlete and her body. That can be sexy too, you know."