Former finalists Elena Dementieva and Jelena Jankovic were eliminated in successive surprises in Arthur Ashe Stadium at the U.S. Open on Thursday.

Blinking back tears and ignoring pain, American teenager Melanie Oudin defeated No. 4-ranked Elena Dementieva 5-7, 6-4, 6-3.

Then No. 5 Jelena Jankovic lost 6-3, 6-7 (4), 7-6 (6) to Yaroslava Shvedova of Kazakhstan in a 2 hour-40 minute match. Jankovic reached the final in 2008, but she said she wasn’t focused on this day: Her grandmother died on Wednesday.

“I was very sad and emotionally I was really not on court,” Jankovic said. “I really tried my best to be there and to try to play, but it was really hard.”

The losses by Dementieva and Jankovic mean half of the top 20 seeded women are out of the draw. No. 23 Sabine Lisicki of Germany also is gone, having left in tears as she was taken away in a wheelchair after injuring her ankle at the end of a 6-3, 3-6, 7-5 defeat against Anastasia Rodionova of Australia.

No. 1 Dinara Safina nearly joined the parade of surprising exits, turning in her second poor performance of the week before hanging on to edge 67{+t}{+h}-ranked Kristina Barrois of Germany 6-7 (5), 6-2, 6-3.

“Another tough day in the office,” said Safina, who double-faulted 15 times, including three in the tiebreaker. “There is no problem in the technique or nothing. Just in my head.”

In other action, 2007 finalist Novak Djokovic cruised by Australian qualifier Carsten Ball 6-3, 6-4, 6-4. Also winners were No. 8-seeded Nikolay Davydenko, No. 10 Fernando Verdasco and No. 14 Tommy Robredo of Spain, No. 15 Radek Stepanek of the Czech Republic, No. 20 Tommy Haas of Germany, and Americans James Blake, Sam Querrey and Jesse Witten, a qualifier ranked 276th. French Open runner-up Robin Soderling advanced when opponent Marcel Granollers of France, quit during the third game with a back injury.

On the women’s side, 2004 champion Svetlana Kuznetsova, No. 9 Caroline Wozniacki of Denmark, No. 13 Nadia Petrova of Russia, No. 21 Zheng Jie of China and No. 24 Sorana Cirstea of Romania progressed. No. 19 Patty Schnyder, No. 30 Alona Bondarenko of Ukraine lost.

Oudin, aged 17 and ranked 70th, played most of the third set with a heavy wrap on her left thigh, while cramps briefly reduced her to tears as she headed to the baseline to serve.

“First time playing on Arthur Ashe, I was beating No. 4 in the world, about to beat her,” Oudin said. “Just a little bit of everything. A lot of things were going through my mind.”

The match ended with a loud shriek when she painted the backhand corner with her serve on her third match point.

She set up a third round match against 2006 champion Maria Sharapova, who eliminated another 17-year—old American, Christina McHale 6-2, 6-1 at night. The 381{+s}{+t}-ranked McHale was a wild-card entry who didn’t really challenge Sharapova.

Looking ahead to facing Oudin, Sharapova said: “I definitely have to go out there and expect her to play some of her best tennis.”

Dementieva, meanwhile, leaves Flushing Meadows with the more accomplished resume -- 14 titles, 14 runner-up finishes, more than $12 million in career earnings -- but still in search of her first Grand Slam title. She was the runner-up here in 2004.

After Thursday’s loss, Dementieva said she was impressed with America’s new break-out player.

“She was in the court, not afraid to play, playing very aggressively, really enjoying this atmosphere and the crowd support,” Dementieva said. “It looks like she has a good future.”

Shvedova met Oudin in the locker room after her win over Jankovic.

“I said, ‘Thanks, you inspired me,”’ Shvedova said.

After saving two match points, Shvedova closed out Jankovic in the third-set tiebreaker with her sixth ace after setting up her match point with an overhead slam to end a long rally. It was her first win over a top 10 player.

“It felt like I was on the court all day,” she said.

The Williams sisters won their opening doubles 6-2, 6-2 over Julia Goerges of Germany and Arantxa Parra Santonja of Spain, answering the questions about whether Venus would play in that event because of her sore knee.

“I actually felt pretty good today,” Venus said. “I’m going to definitely be in both events.”

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