NEW YORK — Jelena Jankovic bent over her racket, leaned against a back wall with a towel pressed to her face, and sprawled on her stomach in the middle of center court.

Then the No. 2 seed gutted her way into the third round of the U.S. Open.

Jankovic outlasted Sweden's Sofia Arvidsson 6-3, 6-7 (5), 7-5 today on yet another uncharacteristically mild August day in Flushing Meadows.

The combination of not being in match condition following a summer knee injury and an array of hard forehands and well-placed drop shots by Arvidsson left Jankovic fighting to get her wind during the 2 hour, 44 minute match at Arthur Ashe Stadium.

"That was a really tough one," said Jankovic, who has reached the fourth round in the first three Grand Slam events this year. "As you can see, I am completely out of breath. She really pushed me to the limit."

Jankovic twice served for the win in the middle set against Arvidsson, yet couldn't put her away — even with a match point in reach. Jankovic held off Arvidsson in a back-and-forth third set when both had trouble holding serve.

When Arvidsson fired long on the final point, Jankovic had her third service break of the third set and eighth overall. There was suddenly a spring in her step as she waved and blew kisses to the crowd.

Even with the squandered chances on her serve, Jankovic still had an opportunity to advance without going the distance. She jumped to a 3-0 lead in the second set tiebreak before losing six straight points. Jankovic extended the set by winning two points on her serve, but fired wide as she approached the net — drawing an exuberant "Yeah" from Arvidsson.

Several times, Jankovic hunched over and leaned on her racket but didn't appear to be in distress. The Serb, who held the No. 1 ranking earlier this year, lost in the fourth round at Wimbledon after injuring a knee in the previous match.

If anything ailed her other than fatigue Wednesday, it wasn't evident in the decisive third set when she raced to a 3-0 edge. Jankovic doubled over again when a fortuitous shot by Arvidsson crept over the net after it smacked the cord in the fourth game, but that appeared more out of exasperation than discomfort.

After a drop shot eluded her dive, Jankovic dropped to the court face down and stayed there for several moments. If anything, it gave her a brief rest.

"I'm still not yet at my full potential, but I'm trying my best," said Jankovic, whose serve was broken twice in each set. "I am still a long way from where I want to be."

While Jankovic escaped an early exit, No. 8 seed Vera Zvonareva couldn't. Zvonareva was upended by Tatiana Perebiynis 6-3, 6-3 in the tournament's biggest upset yet. Svetlana Kuznetsova shook off an early break and rallied to a 7-6 (3), 6-1 victory over Sorana Cirstea.

In men's first-round play, fifth-seeded Nikolay Davydenko beat Dudi Sela 6-3, 6-3, 6-3; No. 18 Nicolas Almagro eliminated Frank Dancevic 6-3, 6-4, 7-5; and Jo-Wilfried Tsonga, the No. 19 seed, moved on with a 6-7 (3), 6-4, 6-2, 6-3 win over Santiago Ventura.

The afternoon session on Day 3 at the Open also featured No. 3 seed Novak Djokovic, who followed countrywoman Jankovic onto center court.

Andy Roddick, who has battled a shoulder injury this summer that led him to skip the Beijing Olympics, was scheduled to close out the night session Wednesday against Fabrice Santoro — the oldest man in the draw at 35. The third night traditionally showcases the first men's match of the second round, but this year that was saved until Thursday.

All women's matches Wednesday were second-round pairings — including No. 23 Lindsay Davenport against Alisa Kleybanova in the first match at night.

Kuznetsova, the 2004 champion and No. 3 seed this year, trailed 4-2 in the opening set before getting back on serve and eventually forcing a tiebreak that she dominated against her inexperienced opponent. She cruised to a 5-0 lead in the second and closed out the match in 1 hour, 13 minutes.

The No. 15 seed Patty Schnyder also moved into the third round with a 6-3, 6-3 win over Anastasia Pavlyuchenkova, the U.S. Open girls' singles champion two years ago. Fifth-seeded Elena Dementieva advanced over Pauline Parmentier 6-2, 6-1, but No. 25 Francesca Schiavone was knocked out by Anne Keothavong 6-2, 3-6, 6-4.