The Bar is High Bar is raised for U.S. and China gymnasts China won the women's title at the 2006 Worlds. The U.S. won in 2007. Next up: Beijing Games.

In ponytails and leotards, they do not look much like warriors.

Uniformly tiny, delicate as Chinese porcelain, Shawn Johnson, Nastia Liukin and the 17 other female American gymnasts, who will be competing here at the 2008 U.S. Olympic trials, beginning Friday, more closely resemble teenage slumber-partiers than world-class athletes.

And yet in August, after the Wachovia Center competition has helped cull the top nine from an extraordinarily deep pool of U.S. talent, those same girls will be on the front line in what promises to be 17 days of heavy-medal warfare between their nation and China at the Beijing Olympics.

The world-champion U.S. women and their cartwheeling Chinese rivals, who will be performing before fanatically partisan and eagerly expectant home crowds, could produce the most compelling drama of the entire 2008 Games.

"Everybody is talking about it," said Jaycie Phelps, a member of the gold-medal-winning U.S. gymnastics team at the 1996 Games in Atlanta and the U.S. Olympic Hall of Fame. "They're the two top teams in the world. China's at home. It should be incredibly exciting."

With once-powerful programs in Russia, Romania and other former Eastern Bloc nations yet to recover from the dissolution of the Soviet Union, the Chinese and U.S. women have vaulted to the top of the gymnastics world.

They combined to win nine of the 15 medals at the 2007 world championships in Stuttgart, Germany. The U.S. edged China by 0.95 of a point to take the team title there. Romania was a distant third.

That result constituted a reverse flip from the 2006 world championships when China beat the Americans by 0.85.

The anticipation of this Olympian rubber-match, made spicier by increasing political and economic tensions between the world's reigning superpower and its Asian heir-apparent, is evident in both countries.

In China, tickets for the 10 days of men's and women's competition, which begins Aug. 10 at Beijing's 19,000-seat National Indoor Stadium, were sold the instant they became available.

NBC, expecting that women's gymnastics again will produce the largest TV audiences in the U.S., has scheduled it as a centerpiece in its record 3,600 hours of coverage. The competition will be shown live in prime time beginning two days after the opening ceremonies, when Olympic interest is highest.