"Right now this team is in pain," said Luciana Aymar, considered to be the best player in the world. "The United States is not at our level, but they have improved a lot. These things happen to all teams."
Argentina has won the world title twice, including last year, while Aymar is a seven-time recipient of the game's world player of the year award. Las Leonas, as the team is known in Spanish, had never lost a game in Pan American play since the sport was included in 1987. The U.S. is ranked 13th.
After the win, the American women stood with their arms on each other's shoulders on the medal podium, and then raised joined hands to the sky when the United States was announced as the winner.
Aymar, meanwhile, wiped away tears, put her hand to her forehead and then stared at the ground. Eventually, she crossed her arms across her chest, the posture assumed by almost the entire team. A few stood with hands on hips, openly disgusted.
The Americans shocked Argentina with two early goals. Paige Selenski scored in the 12th minute and Shannon Taylor added another in the 15th. Maria Barrionuevo scored on a penalty corner in the 18th for Argentina, but O'Donnell made it 3-1.
Barrionuevo scored her second on a penalty in the 42nd before Michelle Vittese secured the win with a goal in the 66th.
"In our minds we never had the lead, it was always 0-0," U.S. captain Lauren Crandall said. "We were always fighting, always working. Argentina is capable of scoring three goals in a minute. We stayed focused to the end -- well let's say the last 5 seconds."
Crandall has been to London before, and she said her parents -- Amy and Tim Crandall of Doylestown, Penn. -- were already looking to book a hotel room just seconds after the match ended.
"I can guarantee you my mom is doing it right now," she said. "They are probably blowing up my phone right now."
The United States finished eighth at the 2008 Olympics, but Australian-born coach Lee Bodimeade figures this bunch could contend.
"Our goal is a medal in London," he said. "Now that we've beaten the world's No. 1 team, well, by definition we've got a chance."
The Americans play the South Americans several times a year, and in February the United States lost to Argentina 3-2 in the Four Nations tournament in Mendoza, Argentina.
"We play Argentina so often," Bodimeade said, "and we've been beaten often enough by them to know what works and what doesn't."
Copyright 2011 by The Associated Press