Rose Lavelle scored the only goal as the United States defeated Canada 1-0 in the four-nation SheBelieves Cup on Thursday to extend the world champions' two-year unbeaten streak.
Manchester City star Lavelle lashed home a low finish on 79 minutes soon after coming on as a second-half substitute to finally break a desperate Canadian defensive effort at Orlando's Exploria Stadium.
Lavelle's 15th international goal gave the US women a 15th consecutive victory, and stretched the team's unbeaten run to 35 games.
The reigning world champions have not lost a game since a defeat to France in January 2019.
On Thursday, Vlatko Andonovski's side dominated for long periods but were denied by a combination of poor finishing and brave goalkeeping from Canada's Stephanie Labbe, who replaced starting keeper Kailen Sheridan after only 10 minutes.
Brazilian-born attacker Catarina Macario spurned an early chance when she blasted high and wide after being played into space by Lynn Williams in the 20th minute.
Carli Lloyd then forced a good reflex save from Labbe, the Canadian keeper leaping to tip the striker's header over the bar.
At the other end, Canada should have taken the lead in the 38th minute when an unmarked Janine Beckie shot straight at US goalkeeper Alyssa Naeher.
Labbe thwarted the US again soon afterwards, diving at full-stretch to parry Williams' venomous strike from outside the area in the 39th minute.
Canada continued to live dangerously and almost conceded on the stroke of halftime before clearing after a scramble on the goal-line following Megan Rapinoe's long-range shot.
Rapinoe forced another save from Labbe soon after the break, the Canadian keeper blocking the US forward's volley.
Canada then wasted yet another glorious chance when Nichelle Prince went sprinting through on goal.
The 26-year-old could have shot herself, but unselfishly squared to an unmarked Beckie who shot straight at Naeher.
A trio of star-studded substitutes piled the pressure on Canada, with US World Cup winners Alex Morgan, Christen Press and Lavelle entering the fray on 64 minutes.
Morgan made an instant impact, heading just wide from Crystal Dunn's cross on 69 minutes.
The breakthrough finally came in the 79th minute when Canada failed to clear a free-kick from the right flank, allowing Lavelle to lash home a low strike through a crowded six-yard box.
The US now face Brazil in the second round of SheBelieves fixtures on Sunday.
The Brazilians opened their campaign earlier Thursday with a 4-1 rout of South American rivals Argentina.
Argentina's preparations for the game had been rocked just hours before kick off after four of their players were ruled out due to a positive Covid-19 case in their squad.
An impressive Brazil proved too powerful for their rivals, with captain Marta scoring from the penalty spot to give her team the lead on 29 minutes.
Goals from Beatriz, Adriana and Geyse Ferreira completed the Brazil scoring while Mariana Larroquette scored a consolation goal for Argentina.