The United States needed three second-half goals to see off Martinique 3-2 in its second Group B match at the 2017 Gold Cup.
Bruce Arena made eight changes from the lineup that opened with a disappointing 1-1 tie against Panama last weekend, including giving Diego Roldan his U.S. debut.
The second goal of a Jordan Morris double helped the Americans avoid an embarrassing defeat despite fielding a side missing many of its senior team members.
"We're certainly guilty of making the game a lot more difficult on us than it needed to be," Arena said after the match, while adding he thought his team played well.
The Americans improved to 5-0-5 since Arena returned for a second stint as national team coach, replacing Jurgen Klinsmann.
The U.S. nearly opened the scoring from a set piece in the 11th minute after Paul Arriola was fouled just outside the Martinique penalty area and Morris's headed attempt from a Kellyn Acosta free kick drifted just wide of the goal.
Morris then set up Juan Agudelo in the 26th minute after the New England Revolution striker made a nice run down the left flank, but his shot from 12 yards was blocked by the Martinique defense.
Three minutes later, Gyasi Zardes had a great look at goal after Agudelo set him up in the center of the area, but he scuffed his shot right to goalkeeper Kevin Olimpa.
Kevin Parsemain then went close twice for Martinique, firing a volley wide on a 32nd minute counter-attack and hitting the post from close range after a missed tackle from Matt Hedges in the U.S. defense.
And Martinique would go close once more before the break, with Stephane Abaul's header from a corner narrowly missed to the left of Brad Guzan's goal and the teams went to the break level at 0-0.
Arriola almost broke the deadlock to start the second half, but his lunging effort just in front of the Martinique goal crashed off the crossbar.
The opener finally came for the Americans when Arriola's shot from distance was blocked right to the feet of Omar Gonzalez and he poked home from close range to give the U.S. the breakthrough it was looking for.
And Morris would double the lead for the U.S. 10 minutes later, beating the Martinique defense to a ball at the near post from an inch-perfect Eric Lichaj pass.
Martinique struck back two minutes later, though, with Abaul setting up Parsemain for a right-footed shot from 18 yards away that Guzan should have done better to save.
And shockingly, the U.S. found itself on level terms in the 76th minute, when a Parsemain shot took a wicked deflection and looped over Guzan's head and into the goal.
Tied 2-2, the U.S. struck back through Morris, who blasted a first-time shot into the roof of Olimpa's net from a well-placed Zardes pass across the center of the penalty area for his second goal of the match.
The Americans finish group play on Saturday against Nicaragua, while Martinique faces Panama on the same day.