NEW YORK — Forget about forehands and backhands. Melanie Oudin's biggest weapon is her heart.
The 17-year-old sparkplug from Georgia proved it again Monday at the U.S. Open, extending her remarkable run to the quarterfinals with another come-from-behind victory, 1-6, 7-6 (2), 6-3 over 13th-seeded Nadia Petrova.
Oudin staved off four points that would have put her behind 5-3 in the second set, then rolled through the third, hitting corners with those underrated groundstrokes and taking advantage of 22 unforced errors by her more-seasoned, higher-ranked opponent.
Rankings, like her age, however, are nothing but numbers.
The 70th-ranked player already had wins over No. 4 Elena Dementieva and No. 29 Maria Sharapova at Flushing Meadows, along with one over former No. 1 Jelena Jankovic at Wimbledon. Now, she's knocked off No. 13.
This time, however, she wasn't the one crying tears of disbelief. It was her twin sister, Katherine, sobbing in the stands.
"I'm so happy to be in my first quarterfinal Grand Slam everrrr," Oudin said in her postmatch on-court interview.
Talk about heart. Oudin improved to 6-1 at Wimbledon and the U.S. Open this year when she's lost the first set. She is 17-4 overall this year in three-set matches.
"I started serving better, thought I could do it and — I did," she said.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
NEW YORK (AP) — When the Grand Slams roll around, the best stories often revolve around the prospect of Williams vs. Williams, Maria Sharapova, maybe even a possible breakthrough by No. 1 Dinara Safina.
All those options have vanished from the U.S. Open, replaced in large part by the potential of Kim Clijsters, the former No. 1 who now brings her baby to work.
Clijsters defeated No. 3 Venus Williams on Sunday, 6-0, 0-6, 6-4, leaving Venus' sister, Serena, as the only top-five player left in a draw that was turned upside down in Week 1 by upsets, comeback stories and the youth movement.
"It's still kind of hard to believe," Clijsters said. "But then again, I'm not trying to get carried away with it all."
But the door is open for the 2005 champion, on the comeback after a two-year hiatus during which she gave up tennis to have a baby.
The baby, 18-month-old Jada, is a regular up in the players' lounge and Clijsters is looking like she might be a fixture on the tour again.
She's a threat this week based on the strength of her own play, and also thanks to the other surprises that went down over a wild first week at Flushing Meadows.
_Safina went home frustrated after a third-round loss, meaning the quest for her first major title will have to wait until next year.
_Sharapova is gone, too, courtesy of 17-year-old Melanie Oudin, whose fourth-round match was scheduled for Monday.
_No. 5 Jelena Jankovic lost earlier in the week and No. 7 Vera Zvonareva blew six match points Sunday to join all the others seeded in single digits on the sidelines.
In early action Monday, Kateryna Bondarenko put a 6-0, 6-0 thumping on Gisela Dulko to advance to the quarterfinals in a section of the draw that doesn't have any seeded players left.
On the men's side, No. 12 Robin Soderling, who upset Rafael Nadal en route to the French Open final, advanced to his first U.S. Open quarterfinal when eighth-seeded Nikolay Davydenko retired with a leg injury at the start of the fourth set.
One of the few things that has gone to form on the women's side has been the play of No. 2 Serena Williams, who advanced easily with a 6-0, 6-2 victory over No. 22 Daniela Hantuchova.
Serena, trying for her third major of the year, has not been challenged yet in this tournament.
"I just want to keep this level and just stay focused," she said.
Even if she does, the Williams-Williams semifinal that seemed all but carved into the bracket before this tournament began could now easily wind up Clijsters-Williams.
Given the way she played against Venus, who's to say Clijsters can't be a threat to Serena, as well?
"With the kind of training that she's put in, I knew this wasn't just for fun," said Clijsters' husband, Brian Lynch, an American who ended his professional basketball career in Belgium when she decided to unretire. "She was trying to make something happen here."
When she was at her peak, Clijsters was one of the few players who had the mobility and power to hang with the Williamses. The whole package was on display Sunday in Arthur Ashe Stadium.
They got off to an awkward start, trading 6-0 sets in a rarity — the first time players have exchanged bagels in a Grand Slam since the 1998 French Open — but then settled in to a back-and-forth third, in which Clijsters came out ahead.
Clijsters grabbed an early break for a 3-1 lead, then served out the match from there, though it was anything but routine.
She fell behind 0-30 on her serve at 5-4, but just kept banging away. She got it to 30-40, then hit a shot deep into the corner that Williams couldn't handle. She forced an error at deuce with another deep groundstroke, then skidded a service winner off the line on the backhand side for the win.
She became the first female wild-card entrant to reach the U.S. Open quarterfinals and could become the first unseeded player to make the Open final since 1997, when Venus did it. She has no world ranking yet because she hasn't played enough tournaments since she came back.
When the latest match was over, Venus Williams conceded that a knee injury she suffered in the first round, which required heavy tape, might have hindered her efforts.
"I wasn't able to play 100 percent," she said.
Nor was Nadal, the headliner on the men's side Sunday.
He overcame a 10-minute medical break for an injury to his stomach muscles to defeat 32nd-seeded Nicolas Almagro, 7-5, 6-4, 6-4.
Nadal missed Wimbledon with sore knees, and now must deal with injured abs that first cropped up last month in Cincinnati.
"I don't want to talk about injuries," Nadal said. "Sorry. No, no, I am a little bit tired to talk about injuries. I am here to try my best every day."
No. 2 Andy Murray also advanced with a 6-3, 6-2, 6-2 victory over American Taylor Dent.
And while the women's draw has gone haywire, the men's is going to form — in an historic way: This marks the first time 14 of the top 16 seeds have advanced to the fourth round of the U.S. Open.
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