Sam Mewis scored the only goal as the United States maintained their remarkable unbeaten streak on Thursday with a 1-0 victory over Portugal in a women's international friendly in Houston.
Mewis nodded in the winner on 76 minutes, heading home from close range after an inviting corner from Manchester United star Christen Press.
The US women almost doubled the lead moments later, but veteran striker Carli Lloyd was ruled offside after tucking away a rebound from Lindsey Horan's free-kick.
Thursday's victory stretched the reigning world champions' unbeaten run to 40 games.
The American women have not been beaten in any fixture since suffering a friendly defeat to France in January 2019.
The US play Jamaica on Sunday before facing Nigeria on June 16 as they build towards next month's Olympic Games in Tokyo, where they will be aiming to regain the crown lost at the 2016 Rio de Janeiro games.
The US complete their Olympic preparations next month with two games against Mexico before heading to Japan.