WIMBLEDON, England — They're still counting casualties back home, and so when Zheng Jie completed the biggest victory of her career today at Wimbledon, she resisted any temptation to leap or squeal or pump her fist or collapse to the grass in glee.

Instead she merely cracked a slight smile, hoping her family, friends and fans in China could do the same.

The 133rd-ranked Zheng beat new No. 1 Ana Ivanovic 6-1, 6-4. It was the latest in a series of first-week upsets, and one easy to applaud because Zheng is a native of Chengdu, the capital of earthquake-stricken Sichuan province.

"Of course I hope to make people happy with my win," Zheng said. "I want more people to have their homes, be fine and happy."

Zheng's third-round victory, her first against a top-10 player, meant the earliest exit by a top-ranked woman at Wimbledon since Martina Hingis lost in the first round in 2001.

Ivanovic nearly departed in the second round. Zheng was watching on TV when the Serb won a reprieve Wednesday by skipping a forehand off the net cord to save match point, then rallied past Nathalie Dechy.

"Really lucky," Zheng said. "It gave me more belief, because I see it's very close. I think, `Maybe I have some chance."'

Depending on results in the second week of the tournament, the 20-year-old Ivanovic could lose the No. 1 ranking she earned for the first time by winning the French Open three weeks ago.

She was gracious in defeat and said she's still learning how to play on grass.

"Sometimes you need a punch to realize what you have to work on," she said. "You have to accept that not every shot you're going to hit is going to be perfect. There are going to be quite a few bad bounces. That's something I found a little bit hard to deal with."

Capricious hops mean unpredictable results, and Ivanovic followed to the sideline fellow Serb Novak Djokovic, two-time runner-up Andy Roddick and second-ranked Maria Sharapova.

As usual, the upset trend didn't apply to top-ranked Roger Federer, who won his 37th consecutive match at Wimbledon by beating Marc Gicquel 6-3, 6-3, 6-1. Federer, seeking his sixth consecutive Wimbledon title, will play Lleyton Hewitt, the only other former champion to enter the men's draw.

Others advancing included Marat Safin, who upset Djokovic in the second round, and Mario Ancic, the last player to beat Federer at Wimbledon. Ancic beat fifth-seeded David Ferrer 6-4, 6-4, 6-7 (5), 7-6 (3).

The last American in the men's field, 102nd-anked Bobby Reynolds, lost to Feliciano Lopez 6-4, 7-5, 4-6, 6-4. Reynolds was the only U.S. male to reach the third round, the worst showing by Americans at Wimbledon since 1926.

"Obviously it's discouraging," Reynolds said. "I was the last one, and it's only the third round. That's not something we like to tip our hats to."

The situation was less gloomy for Americans on the women's side, where three players remain. Bethanie Mattek, who has never previously won more than one match at a Grand Slam event, advanced to the fourth round by beating 2007 runner-up Marion Bartoli 6-4, 6-1.

"This is a pretty amazing feeling," Mattek said. "It was pretty cool being able to beat the finalist last year."

Mattek will next play two-time champion Serena Williams, who defeated 2006 champ Amelie Mauresmo 7-6 (5), 6-1. Four-time champion Venus Williams is scheduled to play her third-round match Saturday.

Also advancing was fourth-ranked Svetlana Kuznetsova, who can overtake Ivanovic in the rankings by reaching the final. No. 2 Jelena Jankovic can do so by reaching the semifinals.

The first rain delay of the tournament only postponed Ivanovic's departure. She struggled to put her service returns in play and found herself fooled repeatedly by bounces on the grass, which forced her to hit shots from awkward stances.

Two days after her great escape against Dechy, Ivanovic found herself again one point from defeat standing on the same court on the same side of the same net — the one she kissed to celebrate her reprieve.

Ready to mount another rally, she leaned forward awaiting the serve, stepped into her return, took a big swing — and shanked the ball into the stands, where no lucky bounce could save her.

Ivanovic conceded her new role as the world's top player has been an education.

"It was all new situations," Ivanovic said. "Everyone's going to be so pumped against you."

That was the case with Zheng, mounting a career comeback after she missed much of last year with an ankle injury. She needed a wild card to enter Wimbledon, but she has been at the forefront of her nation's emergence in tennis.

In 2004, Zheng reached the round of 16 at the French Open, the best showing by a Chinese woman in a major event. Two years later at the Australian Open, she and doubles teammate Yan Zi became the first Chinese players to win a Grand Slam title. They also won the doubles title at Wimbledon in 2006, when Zheng climbed as high as 27th in the singles rankings.

Zheng played at the Olympics in 2004 and will play singles and doubles for the home country at Beijing in August. The Olympic tournament will be on hard-court, but Zheng's best surface may be grass, even though she said there's no lawn tennis in China.

Her flat shots are well-suited for grass, and she had the 6-foot-1 Ivanovic bending low for balls.

"I like the grass," Zheng said. "This is why I can win the match."

She said her family and friends were able to watch despite the devastation resulting from the May 12 earthquake, which killed almost 70,000 people and left 5 million homeless.

"I've been lucky because my family is OK, but others haven't been," she said.

Two weeks after the disaster, Zheng played in the French Open, where she reached the third round and sent her prize money home.

"After Wimbledon I want to go back to do some more to support them in my city," she said. "Maybe I will give the money."

Not that Zheng needs more motivation to win Wimbledon, but the women's champion receives $1.5 million. The final will be on her 25th birthday.

Associated Press Writer Rob Harris contributed to this report.