SHANGHAI, Sept. 26 -- COPING with Brazil's finesse is worry enough; the tricky feints, bicycle kicks and showy backheel passes.

The South Americans can also be downright rough, which is a flip side for the United States to deal with in tomorrow's women's World Cup semifinals.

"They're not going to let us hold on to the ball very long," US forward Heather O'Reilly said. "We'll get it stripped or get our legs taken from under us. We need to keep the ball moving and bring our technical game, or else we're going to pay for it."

United States coach Greg Ryan was more direct.

The Americans defeated Brazil 2-0 three months ago in New York, and Ryan said their opponents' main tactic was fouling, "chopping our players down to break up the game's rhythm."

"I expect this game to be very physical," he said. "Our girls will be prepared for it, but it was a very dirty game in June."

The Brazilians won't need much help at Dragon Stadium in Hangzhou, a capital of ancient China famed for West Lake, which is surrounded by low mountains and famous temples and pagodas.

Marta, the FIFA player of the year in 2006, and Cristiane may be the best striker duo in women's soccer. They are supported by a cast of others up front -- Formiga, Daniela and Maycon -- and a street-soccer culture back home that breeds brash moves and flashy goals.

Marta didn't play three months ago, and neither did United States goalkeeper Hope Solo. But many of the younger Americans did, and several were stunned by Brazil's hard tackles -- a growing feature of the women's game.

"It was kind of an eye-opener for a lot of us younger players who haven't played in a physical game like that," 23-year-old US midfielder Lori Chalupny said. "It was much more physical than any game I'd been involved in. We're expecting a lot of the same this time around."

Brazil picked up its five yellow cards in the first half, and led 20-11 in fouls. The Americans led in everything else, capped by goals from their striking pair of Kristine Lilly and Abby Wambach.

Wambach has four in the World Cup, one behind tournament co-leaders Marta and Norway's Ragnhild Gulbrandsen.

Undefeated in 51 games and seeking its third title to go with World Cup in 1991 and '99, the United States is a slight favorite to reach Sunday's final in Shanghai against either defending champion Germany or Norway.

They play Wednesday's other semifinal in Tianjin's Olympic Center Stadium, site of some of next year's soccer in the Beijing Olympics.

The No. 1-ranked United States has lost only one of 22 games to Brazil, but the last three have been very close, including a 2-1 extra time victory in the 2004 Olympic gold-medal game, which Brazil probably deserved to win.

"America is a tough team," said coach Jorge Barcelos, trying to bring Brazil its first women's World Cup title. "They also have some famous players. The only difference is: we have rested one day less than America, and 24 hours is very important for soccer players."

The Brazilians can string a dozen passes together and finish them off with a tap-in. In this tournament, they've also scored on surprise shots from distance -- like Cristiane's 20-meter (yard) winner in the quarterfinals against Australia.

Solo knows Daniela from playing Sweden, which has the world's top professional league.

"She has one of those shots where she can crack the ball from 30 yards out," Solo said. "That's just something I'm going to have to be ready for."

Though they've made the semifinals, the United States has struggled with possession, scoring mostly on set plays and counterattacks. They've looked stiff at times, but may have snapped out of it with a 3-0 victory on Saturday over England in the quarterfinals.

Brazil's defense may help.

"I think we are going to have opportunities to score on them," Solo said. "I'm not so sure they are very organized in the defense like a lot of teams that we do play."

Though the defense is suspect, it's can't be too bad. Brazil has given up only two goals in four games -- the same as the United States.

"We are confident that we have our best soccer ahead of us, and we showed some really good clips of how we can play against England," O'Reilly said. "Every time we've played them it's been a thrilling game. Sometimes a little too thrilling. I can guarantee another one coming up."