Sophia Smith scored a pair of goals to help the United States beat Germany 4-1 and advance to the quarterfinals at the Paris Olympics on Sunday night.
Mallory Swanson and Lynn Williams also scored for the Americans, who defeated Zambia 3-0 in the opener.
The Americans are playing their first major tournament under new coach Emma Hayes, who took over the U.S. team in late May.
Hayes is tasked with leading the Americans as they seek to distance themselves from the disappointment of last summer's Women's World Cup, when they crashed out in the round of 16.
The United States is the winningest team in the Olympics, with four gold medals. The Americans won the bronze medal at the Tokyo Games under former coach Vlatko Andonovski, who resigned following the World Cup.
Smith started for the United States after leaving the opener in the first half with what appeared to be an ankle injury.
Ten minutes into the match, Smith struck a cross from Trinity Rodman that sailed past German goalkeeper Katrin-Ann Berger.
Giulia Gwinn equalized in the 22nd minute with a low, bouncing shot from well outside the penalty area that eluded diving U.S. goalkeeper Alyssa Naeher.
Swanson put the United States back in front in the 26th. Berger punched out an attempt from distance by Smith, but Swanson picked up the rebound for a goal. It was Swanson's third goal of the Olympics.
Swanson is the second player to score three goals in the group at an Olympics, joining Abby Wambach in 2012.
Smith scored her second in the 44th minute on a high-arcing shot that hit the far post and caromed into the goal.
Williams, a substitute, added the final goal in the 89th minute and fans in Marseille chanted "USA! USA!" as time ran down.
U.S. defender Tierna Davidson left the match with an injury and was replaced by Emily Sonnett.
Alexandra Popp left in the 76th minute with what appeared to be a right leg injury. It was a blow to Germany, which was already playing without midfielder Lena Oberdorf (knee).
The United States plays Australia in Marseille to conclude group play. Germany, which defeated Australia in its Olympic opener 3-0, plays Zambia in Saint-Etienne.