By Associated Press | Aug. 03, 2012, 4:56 p.m. (ET)
Maggie Steffens

LONDON -- Maggie Steffens (above) scored three goals and the U.S. women's water polo beat China 7-6 in their final preliminary-stage game to remain undefeated at the London Olympics.

The U.S. finished the preliminary round even with Spain at the top Group A with five points. But Spain earned the top spot because of the tiebreaker, making the Americans the group's second-seeded team for the knockout stage.

The U.S. will play 2012 European champion Italy in Sunday's quarterfinals.

China finished the group stage winless and will play Group B winner Australia in the quarterfinals.