England impressed in their first outing of the year before a stunning second-half goal condemned Mark Sampson's team to a 1-0 defeat against World Cup winners the United States in Tampa.
Captain Steph Houghton was caught out by a sharp turn from substitute Crystal Dunn, who wriggled into the penalty area from the left and found the far top corner with a strike that gave England's California-born goalkeeper Karen Bardsley little chance.
The goal arrived in the 72nd minute, and England could not find the leveller their performance arguably deserved.
Shortly before the hour mark, England spurned a golden chance as Toni Duggan shot straight at Hope Solo when a pass across goal to strike partner Jodie Taylor could have brought England the opener.
They were to regret that, as the visitors fell to defeat in their first match of three at the SheBelieves Cup. After this setback at the Raymond James Stadium, home to NFL side the Tampa Bay Buccaneers, England will face Germany on Sunday and France next Wednesday.
Against a side that had already played six internationals this year, winning them all with an aggregate score of 28-0, England were far from overawed.
In an all-red kit, they began purposefully and Demi Stokes had an early left-footed shot charged down.
England's XI contained six Manchester City Women players, led by captain of club and country Houghton.
The Lionesses, third at the World Cup last summer, wanted a 35th-minute penalty after the ball rolled off the arm of American defender Becky Sauerbrunn, who came under pressure from Taylor, but they were out of luck.
England had the clearest chance of the opening hour in the 59th minute when Duggan ran behind the US defence to meet a hopeful ball forward from Fara Williams and had a free shot at goal. From a narrowing angle her drive towards the bottom left corner was grasped by Solo as unmarked Taylor waited in vain for a pass.
It was cruel on England to fall behind but the finish was sublime from Dunn.
England swiftly replaced Williams with Karen Carney, and Fran Kirby came on for Taylor up front, but there was no way back.
:: Germany beat France 1-0 in the round-robin tournament's opening match, Leonie Maier scoring an 84th-minute winner.