BEIJING — A few fun-loving fresh faces have suddenly turned Jamaica into the "World's Fastest Nation."

And that supposed U.S. track and field juggernaut? Well, things aren't quite going to plan.

Right fist thrust overhead as she crossed the finish line all alone, silver braces shining in the Bird's Nest lights as she hopped in celebration like the 21-year-old she is, little-known Shelly-Ann Fraser won the women's 100 meters yesterday in 10.78 seconds to help make these Olympics a sweeping success for Jamaica.

Fraser was followed across the line, steps later, by teammates Sherone Simpson and Kerron Stewart, who both finished in 10.98 and both collected silvers — giving Jamaica the first sweep of medals in a women's 100 by any nation at any Olympics or world championships.

That impressive display came one day after Usain Bolt's record-breaking victory in the men's 100 — giving Jamaica the first sweep of men's and women's 100 golds at any Olympics since 1988.

Not bad for a nation of 2.8 million, about the population of Chicago. Not bad for a nation that long has produced top sprinters but never an Olympic dash champion, man or woman, before this wonderful 2-for-2 weekend.

"I was speechless yesterday for a while. Today I cried," Jamaica's minister of sport, Olivia Grange, said. "Little Jamaica — our country is blessed with some of the best, if not the best, talent you can find."

Now compare and contrast. The single 100 bronze for the United States, earned by Walter Dix, amounts to the country's worst combined showing in the men's and women's dashes at an Olympics since earning zero medals in the 100 at both the 1980 Moscow Games — where, let's remember, a boycott prevented any Americans from competing — and the 1976 Montreal Games.

"We've dominated for years, and now it's their time," said Lauryn Williams, the 2004 Olympic silver medalist and 2005 world champion — and one of three U.S. women who never mounted a challenge in yesterday's final.

"We're getting a pretty good taste of what it's like to be at the bottom," Williams said.

The United States protested the results in the women's 100, asking that the race be reviewed because of a possible false start by American Torri Edwards — who wound up last. The appeal was swiftly rejected.

Not that a ruling for the U.S. would have made much of a difference. The Jamaicans, particularly Fraser, were so much better that it's hard to imagine the outcome being much different if the race were run again.

It was all part of an all-around rough day for the Stars and Stripes.

In the men's 1,500 meters, two-time Olympic medalist Bernard Lagat, U.S. team flagbearer Lopez Lomong and NCAA champion Leo Manzano — all naturalized citizens making their Olympic debuts for their new country — failed to reach the final.

"I gave everything I had," said Lagat, who won a silver and bronze representing his native Kenya at the past two Summer Games.

There was more bad news when 2004 relay gold medalist Dee Dee Trotter and Mary Wineberg flopped in the women's 400 semifinals.

At least favorite Sanya Richards left everyone in her semifinal well behind by the halfway mark and coasted home in 49.90 seconds, the fastest time by nearly a quarter-second in any of the three heats.

Richards could be part of a stronger upcoming presence for the Americans, with the potential for a sweep in today's men's 400-meter hurdles.

In other finals yesterday, Ethiopia's Kenenisa Bekele (men's 10,000 meters) and Cameroon's Francoise Mbango Etone (women's triple jump) successfully defended their titles from the 2004 Olympics.

Sileshi Sihine gave Ethiopia a 1-2 finish behind Bekele's new Olympic record, but two-time champion Haile Gebrselassie — who cited concerns about pollution in opting not to enter the marathon — finished sixth.

The second world record of the 10-day Olympic track meet came in the Olympic debut of the 3,000-meter women's steeplechase.

Gulnara Galkina-Samitova of Russia became the first woman to go under 9 minutes and clipped more than 2 1/2 seconds off her own mark that had stood since July 2004, finishing in 8:58.81.