Serena, Jankovic, Dementieva advance in Rome

Updated: May 17, 2007, 5:04 PM ET news services

ROME -- Serena Williams' clay-court game is rounding into shape ahead of the French Open.

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Williams appeared frustrated at times but eventually overpowered Shahar Peer of Israel 6-3, 6-3 Thursday to reach the quarterfinals of the Italian Open.

"I feel like everything is coming together," Williams said. "I'm doing everything to stay healthy. That's my goal this year, to stay healthy."

Williams will face 14th-seeded Patty Schnyder, who beat Samantha Stosur 6-4, 6-4.

Third-seeded Jelena Jankovic defeated Alona Bondarenko 6-4, 7-5 and will play Elena Dementieva, who advanced when fifth-seeded Nadia Petrova retired with a lower back injury.

Four months ago, Peer pushed Williams to three sets before losing in the quarterfinals at the Australian Open. Williams went on to win her eighth Grand Slam title.

"It was definitely a good test. She plays a little like [Arantxa Sanchez-Vicario]," Williams said. "She gets a lot of balls back. I knew she was going to be a tough opponent on clay. I thought I did pretty well."

Williams and Roger Federer have a shot at completing a Grand Slam if they win the remaining three majors this season. The French Open begins May 27.

"Hopefully, I'll be playing seven rounds in Paris and winning seven matches. Then after that I'm going to the next Grand Slam," Williams said. "Only two people can do it this year, so I'm one of those two."

Williams came close to the Grand Slam in 2002, winning three majors, but she sat out the Australian Open. She completed her so-called "Serena Slam" by winning in Melbourne at the start of 2003.

Peer's quickness matched Williams' power at the start and neither player held serve until Williams took a 4-2 lead in the first set.

Eventually, Williams' strength won out and she improved to 18-2 this year.

"I've been working out. During the clay-court season you have to get yourself in better shape," Williams said. "All the matches last about a half-hour longer than usual."

Early in the second set, Williams slammed a ball that barely missed hitting a line judge, earning a warning from the chair umpire.

"I felt so bad. Thank God I didn't hit her," Williams said. "Obviously, I was not going for the line judge. But that's what happens when you lose your temper, you can take someone out."

It occurred after Williams missed a first serve.

"I didn't serve well at all today," she said. "I don't think I got one first serve in during that game. But usually when I serve bad at the beginning of a tournament, it gets better."

Second seed Svetlana Kuznetsova had to work harder than expected to reach the quarterfinals when she eased past Yuliana Fedak of the Ukraine, 7-6, 6-1.

Kuznetsova, the highest-ranking player left in the clay-court tournament after the elimination of top seed Amelie Mauresmo on Wednesday, twice failed to serve out for the first set and was 4-1 down in the tiebreak before finding her rhythm.

Fedak, ranked No. 138 in the world, had entered the main draw only as a lucky loser from qualifying.

"It was very hard for me. This is my third week in a row playing tennis and I felt so uncomfortable on the ball in the first set, so it was very frustrating," Kuznetsova said at the courtside.

"But I knew I could play better, so I just tried to concentrate and in the end I started to play better."

Kuznetsova's reward was a last-eight meeting against last year's Rome runner-up, Russian Dinara Safina, who beat Kateryna Bondarenko of Ukraine 6-2, 6-3.

In other action, Daniela Hantuchova eliminated Anna Chakvetadze 6-2, 6-3.

Stosur upset fourth-ranked Mauresmo on Wednesday, but she couldn't get past Schnyder.

"She plays really well on the clay and she's really tricky," Williams said of Schnyder, who was runner-up to Mauresmo two years ago.

Jankovic dropped her serve three times in the second set but held serve on match point.

Petrova had a trainer massage her back after Dementieva broke to take a 4-3 lead in the first set. Dementieva won the opening point in the next game before Petrova called it quits.

"I had an accident in the gym before the tournament," Petrova said. "It was getting better but then when I ran for a ball in the match today, I felt a sharp pain.

"It's a shame. I was really hoping to go far this week. Even today I was showing good tennis."

Petrova did not say whether the injury would prevent her taking part in the French Open, which starts on May 27.

Information from The Associated Press and Reuters contributed to this report.