The United States claimed its quarterfinal berth Saturday at the 2004 Olympics women's soccer tournament, getting second-half goals from Mia Hamm and Abby Wambach to overcome an often superior Brazilian side in Group G play at Thessaloniki.

Hamm converted a 57th-minute penalty kick and Wambach scored following a slicing run from a Lindsay Tarpley header as the Americans improved to 2-0-0 with their second shutout of the Athens Games.

''Brazil had the run of play in the first half, we had it in the second half,'' U.S. coach April Heinrichs said. ''I think our players kept their calm, and the best part about it was that our players responded to the first half and did some self-evaluating. They said to themselves that we have to bring more mentality, more decisiveness and a little more bite to our tackles and ball-winning so we don't spend so much time chasing. … We started to find space, and when you can find space, you could see we pushed the ball around more confidently in the second half.''

Wambach received a yellow card for the second successive match and will miss through suspension Tuesday's first-stage finale against Australia in Thessaloniki's Kaftanzolglio Stadium.

The result renders that clash nearly meaningless. The U.S. women need only a tie to win the group, but Group G's second-place team could receive an easier path to the gold-medal game. That will depend on what occurs in Groups E's and F's final matches following stunning developments in the women's soccer competition.

China was all but eliminated with a 1-1 tie against Mexico in Patras, and Japan followed its stunning victory over Sweden with an equally stunning 1-0 loss to Nigeria in Athens, opening a door for the Swedes to avoid Germany in the quarterfinals.

The Germans, Japanese and Nigerians clinched quarterfinal berths, all benefiting from China's disappointing showing — one point and a minus-8 goal-differential — in its two Group F matches.

Maribel Dominguez's breakaway goal gave Mexico an 11th-minute lead Saturday, but Ji Ting pulled China even in the 34th. Mexico needs only to avoid an eight-goal loss Tuesday to Germany to reach the final eight advances to the final eight. China needs Nigeria to upset Sweden to get through.

The Group E winner has the seemingly simplest path to the championship game, not having to face another group winner until the final. World Cup runner-up Sweden appeared to surrender the spot to Japan in Wednesday's loss, but the Japan failed to nail it down against Nigeria. Vera Okolo's goal 10 minutes into the second half led the Super Falcons.

The Swedes, who face Nigeria in Volos, will win the group with a victory of two or more goals, or a one-goal win in which they score at least twice. A 1-0 Sweden victory would lead to a draw to assign the Nos. 1, 2 and 3 spots, with No. 3 slated to face the Group G winner. Nigeria wins the group, and Sweden the final quarterfinal berth, with a tie.

Things are more straightforward in Group G, where host Greece (0-2-0, minus-4 goal-differential) needs to upset Brazil (1-1-0, minus-1) in Patras and make up a goal-deficit to the Aussies (1-1-0, even) or Brazilians. Australia on Saturday scored a 1-0 victory over Greece in Heraklio; Heather Garriock scored the goal.

Brazil dominated the first half against the Americans, possessing almost at will and creating several chances behind a creative midfield and dangerous attacking trio of Marta, Pretinha and Cristiane.

Brazil outshot the Americans, 6-2, in the first half, putting five shots on target and twice hitting the frame, with Formiga's spinning shot in the 14th minute hitting the crossbar after dipping over goalkeeper Briana Scurry, and Cristiane finding the right post when Marta presented her an open net in the 31st.

''[Brazil is] unbelievable on the ball,'' Hamm said, ''and they are some of the most exciting players in the world to watch, and some of the most frustrating to play against, because they can make you look like you've never played soccer before.''

The Americans answered by switching from a 4-4-2 formation to a 4-3-3 in the second half, with Kristine Lilly joining Hamm and Wambach up top. Lindsay Tarpley's entrance in the 57th minute, for Aly Wagner, gave the Americans the upper-hand in midfield.

Tarpley came on before Hamm's penalty kick but after Monica took down Wambach in the box. Monica was cautioned and will miss Brazil's clash with Greece after receiving a second yellow card.

The second goal came from a Christie Rampone throw-in that Heather O'Reilly flicked on to Tarpley, who beat a defender to the ball, forcefully heading it up the right flank. Wambach tracked it down, cut to her left, then split Monica and Juliana, running square across the goal. Wambach fired left-footed to the near post.

U.S. SUMMARY
Saturday, Aug. 14 at Thessaloniki, Greece

United States 2 Brazil 0. Goals: Hamm pen. 58, Wambach 77.

United States — Scurry; Rampone, Fawcett, Reddick (Mitts, 80), Markgraf; Boxx; Foudy, Wagner (Tarpley, 57), Lilly (O'Reilly, 69); Wambach, Hamm.

Brazil — Andreia; Monica, Tania, Juliana, Daniela; Rosana (Kelly, 72; Grazielle, 85), Formiga, Elaine; Pretinha, Marta, Cristiane (Maycon, 65).

Yellow cards: U.S. — Wambach 49, Rampone 89; Brazil — Monica 57.

Referee: Dagmar Damkova (Czech Republic).

Att.: 17,123.

2004 ATHENS OLYMPICS
WOMEN'S FOOTBALL

Group E
W L T GF-GA Pts
x-Nigeria 1 0 0 1-0 3
x-Japan 1 1 0 1-1 3
Sweden 0 1 0 0-1 0
x – qualified for quarterfinals

Wednesday, Aug. 11
Sweden 0 Japan 1 (Arakawa 24)

Saturday, Aug. 14
Japan 0 Nigeria 1 (Okolo 55)

Tuesday, Aug. 17
Sweden vs. Nigeria at Volos

Group F
W L T GF-GA Pts
x-Germany 1 0 0 8-0 3
Mexico 0 0 1 1-1 1
China 0 1 1 1-9 1
x – qualified for quarterfinals

Wednesday, Aug. 11
Germany 8 (Prinz 13, 21, 73, 88, Wunderlich 64, Lingor pen. 76, Pohlers 81, Mueller 90) China 0

Saturday, Aug. 14
China 1 (Ji Ting 34) Mexico 1 (Dominguez 11)

Tuesday, Aug. 17
Germany vs. Mexico at Athens

Group G W L T GF-GA Pts
x-United States 2 0 0 5-0 6
Australia 1 1 0 1-1 3
Brazil 1 1 0 1-2 3
Greece 0 2 0 0-4 0
x – qualified for quarterfinals

Wednesday, Aug. 11
Greece 0 United States 3 (Boxx 14, Wambach 30, Hamm 82)
Brazil 1 (Marta 36) Australia 0

Saturday, Aug. 14
Greece 0 Australia 1 (Garriock 27)
United States 2 Brazil 0 (Hamm pen. 58, Wambach 77)

Tuesday, Aug. 17
Greece vs. Brazil at Patras
United States vs. Australia at Thessaloniki

Quarterfinals
Friday, Aug. 20
F1 vs. E2 at Patras
G1 vs. E3/F3 at Thessaloniki
F2 vs. G2 at Heraklio
E1 vs. G3 at Volos

Semifinals
Monday, Aug. 23
Patras winner vs. Thessaloniki winner at Heraklio
Volos winner vs. Heraklio winner at Patras

Bronze Medal
Thursday, Aug. 26
Semifinal losers at Athens

Gold Medal
Thursday, Aug. 26
Semifinal winners at Athens

Goalscorers
Birgit Prinz (Germany) 4
Mia Hamm (U.S.) 2
Abby Wambach (U.S.) 2
Eriko Arakawa (Japan) 1
Shannon Boxx (U.S.) 1
Maribel Dominguez (Mexico) 1
Heather Garriock (Australia) 1
Ji Ting (China) 1
Renate Lingor (Germany) 1
Marta (Brazil) 1
Martina Mueller (Germany) 1
Vera Okolo (Nigeria) 1
Conny Pohlers (Germany) 1
Pia Wunderlich (Germany) 1