SHANGHAI, China -- Lori Chalupny has experienced three decisive moments in China.The first threatened her soccer career. The last were much better: two eye-catching goals for the U.S. national team's quiet midfielder. The latest goal came Tuesday after just 57 seconds, the second-fastest in tournament history. It sent the No. 1-ranked Americans past Nigeria 1-0 and into the quarterfinals of the Women's World Cup. "That goal, being my first World Cup goal, was an amazing feeling"' said Chalupny, a former defender prone to menacing late runs. On the Nigeria goal, she stabbed in a close shot off a header from Abby Wambach. Her other China goal came eight months in the Four Nations tournament, where Chalupny's soaring 20-yard strike helped beat China 2-0. ``That goal was a big confidence builder for me, showing that I can make a difference in these games,'' said Chalupny, who will guide the midfield in Saturday's quarterfinal against England in the northern industrial city of Tianjin. Another quarterfinal Saturday has North Korea facing defending champion Germany in the central city of Wuhan. Chalupny (pronounced ka-LUP-nee) also had a scary moment almost two years ago in China. Playing in a tournament, she sustained the last in a series of concussions and was sidelined three months. "I got hit in the nose, and I had concussions before in college, but this was icing on the cake," she said. "I feel I am 100 percent over it and I'm not thinking back toward it. When you are out on the field you can't afford to be timid or afraid." As the American forwards struggle to score in the World Cup, Chalupny, Shannon Boxx and Carli Lloyd provide the biggest threats out of midfield. On paper, the U.S. appears in good shape to win its third World Cup title. But the Americans, who are undefeated in 50 straight games, were stretched in their first three games in Group B -- by far the best in the tournament -- against No. 3 Sweden, No. 5 North Korea and five-time African champions Nigeria. The group was so good that Sweden -- runner-up four years ago -- failed to advance. Several other strong teams will also fail to make it when the last group games are completed Thursday. Then there are rising powers in Brazil, North Korea and host China. "Overall there is great parity," American coach Greg Ryan said. "The top teams are no longer the top teams by miles." The U.S. has scored five goals in three games -- three by Wambach. But it has missed dozens of other chances, a slightly worrying trend with the Sept. 30 final in Shanghai in sight. "You never put a lot of pressure on goal scorers or they will miss more," Ryan said. "The main thing for us is to continue creating our chances knowing at some point they just start falling. We just hope it's soon." The Americans have been relying on set plays and a stellar defense. They probably were slowed by a few wet fields -- training in California has not prepared the team for rain. "We don't typically play in downpours and on wet slippery fields," Ryan said, referring to Tuesday's rain-soaked game, which was played as Typhoon Whipa was nearing. "We just haven't had that experience. I guess we should have hosed down our fields to get ready for this." Fallout from the typhoon forced two games scheduled for Wednesday to be pushed back to Thursday. In final games in Group C on Thursday, it's Norway vs. Ghana and Australia vs. Canada. In Group D: Brazil vs. Denmark and China vs. New Zealand. Ghana has been eliminated but the other seven still have a chance at the quarterfinals. Brazil, China, Norway and Australia are the favorites. Their group of quarterfinals will be played Sunday in Wuhan and Tianjin. The postponements came 10 minutes after the Australia-Canada game was to have begun, leaving fans outside the stadium to listen to explanations over loudspeakers. "It's disappointing to find out so late about the rescheduling, but that aside it allows all teams to compete on an equal footing," Australia coach Tom Sermanni said.