The U.S. women's water polo team won their group Sunday without getting in the pool.
Hungary, which upset the U.S. last week, dropped a thriller to China to finish at 2-1-1, leaving the U.S. (3-1) alone in first.
In the other group, Australia and the Netherlands each won to finish at 3-1, but idle Spain won the three-way tiebreaker for first.
China pulls upset
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China 11, Hungary 9: China took a big lead, outscoring Hungary 4-1 in the first quarter and 3-1 in the second, before hanging on in a final minute that saw four goals.
Hungary slowly got back into the game and finally cut the deficit to 9-8 on a penalty shot with 54 seconds left. China answered with its own penalty goal 12 seconds later. Hungary forced a player exclusion on offense and scored again to make it 10-9, but the Hungarian defense gave up an extra-player goal of its own with one second left.
China finished with two straight wins after losing a close opener to the ROC and a 12-7 decision to the United States. Hungary dug itself a big first-half hole, getting outscored 4-1 in the first quarter and 3-1 in the second. MATCH STATS
ROC tops Japan
ROC 20, Japan 16: The host nation showed signs of improvement in this tournament but wound up winless. After losing its opener 25-4 to the United States, Japan was much more competitive in its remaining games, losing 16-11 to China and 17-13 to Hungary.
In its final game, Japan turned up the offense but simply couldn't stop the ROC, falling behind 12-8 at the half and 18-12 after three quarters. MATCH STATS
Canada loses tough fight
Netherlands 16, Canada 12: Canada hung around and only trailed 8-7 at the half and 11-10 early in the fourth quarter. The Netherlands pulled away with three straight goals. Canada once again closed to with two with 1:07 to play but conceded twice in the last minute. MATCH STATS
Australia rolls South Africa
Australia 14, South Africa 1: The African representative was outscored 97-7 in four games. MATCH STATS