After being held by the Netherlands in their previous encounter, the Stars and Stripes suffered another painful draw, casting doubt on their chances of winning the event for an unprecedented third time in a row.
Portugal, who could have pulled off one of the greatest upsets in tournament history if they had won, hit the post in the 91st minute with Ana Capeta.
In the end, the United States were relieved to hear the full-time whistle, which was enough to send them through as runners-up to the Netherlands, who hammered Vietnam 7-0.
However, the US were far from their best as they battled to break down a tenacious Portuguese defense, while keeper Ines Pereira made two excellent saves to deny recalled striker Lynn Williams.
The world’s top team will now face the winner of Group G, which will be decided on Wednesday, with Sweden – the last country to upset the USA in a World Cup 90-minute game – poised to finish first unless there is a 10-goal swing.
On a tough night in Auckland for the four-time world champions, midfielder Rose Lavelle was cautioned and will miss the next game after receiving her second warning of the tournament.
The United States fails to impress.
The United States entered this competition as heavy favorites to win, but they have failed to please their thousands of traveling fans in New Zealand.
They complete the group stage with five points, two behind the Netherlands, and concerns about why they appear like a shell of the team that won the World Cup in 2015 and 2019.
Following a 3-0 triumph over debutants Vietnam, the United States was held by the Netherlands in a rematch of the final four years before.
Manager Vlatko Andonovski had picked the same starting XI for the first two games but made two changes as Lavelle, who has recovered from a recent knee injury, came off the bench to assist Lindsey Horan to equalize against the Netherlands.
As Savannah DeMelo and Trinity Rodman withdrew from the World Cup, forward Williams got her first taste of the action.
However, the alterations did not inspire the United States, who failed to score in a World Cup game for the first time since being held 0-0 by Sweden in 2015.
Portugal exits with their heads held high.
Portugal, who finished third in their group, one point behind the United States, will leave the competition with their heads held high after coming so close to causing a massive upset.
They had to play 13 games – 10 group games and three play-off matches – to qualify for their first World Cup, and they only did it with a 2-1 win against Cameroon in February.
After almost losing to the Netherlands in their first group game, Francisco Neto’s side won a historic first win on the global arena, defeating Vietnam 2-0 thanks to goals from Telma Encarnacao and intriguing young prospect Francisca Nazareth.
Portugal’s ability to go into the third group game still in with a possibility of qualifying for the knockout stage will be viewed as development.
They were sturdy at the back and swift on the break against the US, with Jessica Silva missing a fantastic chance in the first half before Nazareth went close.
When substitute Capeta hit the post, the fourth official had just signaled a minimum of eight more minutes.
