Williams edges teen qualifier to reach quarters

ZURICH, Switzerland (AP) -- Former champion Venus Williams was pushed to two tiebreakers over two hours by 16-year-old qualifier Ana Ivanovic of Serbia-Montenegro before reaching the Swisscom Challenge quarterfinals Thursday.

The seventh-seeded Williams edged Ivanovic 7-6 (11), 7-6 (6) and will meet Wimbledon champion Maria Sharapova on Friday.

Elena Dementieva, Patty Schnyder and Nadia Petrova also advanced to the quarterfinals Thursday.

Ivanovic, whose first tour victory came in the first round here, gave Williams, the 1999 champion, a battle, rallying from 4-1 behind in the first set and saving a set point at 6-5 to force the tiebreaker.

In the second set, Williams was 4-2 up before being caught again, then Ivanovic led 6-3 in the tiebreaker. On her third set point, however, she netted the ball and moments later Williams was the winner.

The third-seeded Dementieva, the runner-up at the U.S. Open and French Open, beat Elena Bovina 7-5, 3-6, 6-0 and faces No. 9 Ai Sugiyama next.

Schnyder, the 10th seed and 2002 champion, downed Fabiola Zuluaga 6-4, 6-3 to set up a match against Paola Suarez, who advanced when Emilie Loit quit with a left leg injury while trailing 6-1, 2-2.

The eighth-seeded Petrova overcame Nathalie Dechy 6-7 (6), 6-4, 6-3 and will play Olympic bronze medalist Alicia Molik of Australia next.