Ivanovic seeks improvement

Ana Ivanovic overcame her toughest test so far, prevailing against Russia's

Nadia Petrova to book her place in the quarter-finals.

The 19-year-old Serb cruised to victory in the first set, but a short rain

break revitalised 11th-seeded Petrova, who claimed the second before Ivanovic

hit back in the decider to secure a 6-1 2-6 6-4 triumph.

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"It was very tough, not so much physically as mentally," she said. "I had to

fight for every point because I didn't feel on top of my game.

"Sometimes you have to win these matches and hopefully tomorrow I will have a

chance to play better."

The number six seed now faces Amelie Mauresmo's conqueror, Nicole Vaidisova,

for a place in the semi-finals.

Ivanovic, playing with pink and black strapping on her right knee, enjoyed a

superb start and wrapped up the first set in just 26 minutes.

With Petrova on the ropes, the subsequent half-hour delay offered the 11th seed

the chance to clear her head in the locker room and save four break points at

the start of the second set.

Ivanovic's failure to convert her break-point opportunities seemed to affect

her focus as she dropped her first set of the Championships.

Petrova continued her impressive form in the decider, playing faultless tennis

from the baseline to hold her opening service game, and was 2-1 up when the rain

returned.

One hour and 20 minutes later the clouds had parted and sun shone on Court Two,

but Ivanovic was still flustered and lost her next service game to love.

However, the Serb began to get some help from her opponent, who committed a

double-fault when trying to save break point in the next game and did the same

again three games later to leave Ivanovic serving for the match at 5-4.

The heavens then opened once more but, when play eventually resumed an hour a

half later, Ivanovic was not in the mood to hang around, duly rattling off the

three points she needed to book her place in the last eight for the first time.

Vaidisova was forced to endure three rain breaks before disposing of an

out-of-touch Mauresmo, the defending champion, while Marion Bartoli, of France,

caused the second shock of the day by fighting back from a set down to oust

third seed Jelena Jankovic.

The 18th seed booked a quarter-final date with Dutch teenager Michaella

Krajicek, who put out Laura Granville, of the United States.

Fifth seed Svetlana Kuznetsova ended the fairytale hopes of 16-year-old

Austrian Tamira Paszek with a straight-sets win.

Kuznetsova will next play a former champion, either Maria Sharapova or Venus

Williams, who will attempt to finish the one remaining fourth-round match

tomorrow.

Their mouth-watering showdown was switched from Centre Court to Court Three

shortly before 5pm, a massive bonus for those spectators with ground passes who

had been expecting a mixed doubles match instead.

However, their joy was short-lived as just three points were played before the

rain intervened once more, Williams leading 30-15 on her serve.

Almost two hours later play on the outside courts was abandoned for the day,

although officials were clinging to the hope of more play on the two show

courts.