Sophia Smith scored twice for the United States in the opening half and the two-time defending champions kicked off the Women's World Cup with a 3-0 victory over tournament first-timers Vietnam on Saturday.

Lindsey Horan added a goal for the favored Americans, who have won four World Cups overall and are vying for an unprecedented three-peat in this year's tournament.

Vietnam drew comparisons to Thailand, the team the Americans routed 3-0 in in their 2019 World Cup opening game. But Vietnam was surprisingly resilient, kept the game closer than expected, and goalkeeper Tran Thi Kim Thanh stopped Alex Morgan's first-half penalty attempt.

Morgan was knocked to the field clutching her calf after trying for the rebound off her missed penalty, but she quickly returned. It was just her second penalty miss for the United States.

Smith, one of 14 Americans playing in their first-ever World Cup, showed why she was named both U.S. Soccer's Player of the Year and the National Women's Soccer League MVP last year with her two first-half goals.

Smith scored off a pass from captain Lindsey Horan in the 14th minute. Smith and Horan celebrated with a choreographed handshake after the goal. She scored again in first-half stoppage time to make it 2-0 going into the break. The United States was at first flagged as offside before a video review confirmed the goal.

The U.S. team was infused with young talent including Smith and Trinity Rodman after settling for a disappointing bronze medal at the Tokyo Olympics. Among the veterans, 38-year-old Megan Rapinoe made her 200th international appearance against Vietnam.

Rapinoe, who scored in the World Cup final in France and was named that tournament's best player, did not start. She announced before the team left for New Zealand that this would be her last World Cup and she would retire from her professional team at the end of the season.

Rapinoe and midfielder Rose Lavelle, who were both limited by injuries in the run-up to the tournament, both came in as substitutes in the 63rd minute. Rapinoe sported bright blue hair.

The youngest player on the team, 18-year-old Alyssa Thompson, was also a second-half sub.

Horan scored into a wide-open net off a pass from Smith, who was rushed by the goalkeeper and deftly sent the ball back to her. Horan, who was recently engaged, kissed her ring in celebration.

There was early drama when Rodman, the daughter of former NBA great Dennis Rodman and one of the young newcomers on the team, appeared injured after falling hard on her back when she was tackled by defender Tran Thi Thu. Rapinoe warmed up on the sidelines and a stretcher was brought out on the filed, but Rodman stood and returned to the match a few moments later.

Saturday's game was the first meeting between the United States and Vietnam. The Vietnamese lost two exhibition matches ahead of the tournament and fell 9-0 to Spain in a closed-door tune-up match in Auckland last Friday.

Also in Group E are the Netherlands and Portugal, which meet Sunday in Dunedin. Portugal is also making its first World Cup appearance.

The group plays all of their matches in New Zealand, which is co-hosting the tournament with Australia. The United States plays the Netherlands in a 2019 final rematch on Thursday in Wellington.

Should the United States top the group, the team will head to Sydney for the round of 16.

Back home in the United States, a sign was erected on the North Lawn of the White House that said "Go Team USA! We are all behind you."

In:
• New Zealand
• U.S. Women's Soccer Team
• World Cup
• Soccer