Substitute Jaime Ayovi came off the bench to give Ecuador a 1-0 win over the United States at the Red Bull Arena in New Jersey.
Jurgen Klinsmann named a strong side against the South American visitors, but it proved to be in vain as Ayovi scored 11 minutes from time to disappoint the home crowd. It was Klinsmann's third loss since taking over the top job.
The United States appeared largely untroubled by the Ecuadorian attack until the decisive strike.
Walter Ayovi made a left-footed cross to Jaime Ayovi, a 60th-minute sub who wriggled free about 8 yards out. He got in ahead of US substitute Tim Ream, before heading the ball to the left of Howard for his fifth international goal.
Elsewhere, Ronaldinho and Marcelo scored as 10-man Brazil came from a goal down to defeat Mexico 2-1.
While the South American 2014 World Cup qualifying tournament is being played, hosts Brazil are preparing their team with friendly games and Mexico were their victims tonight at the TSM stadium in Torreon.
Things started badly for the five-time world champions as David Luiz sent the ball into the back of his own net in the 10th minute after a Pablo Barrera cross but the left-sided duo spearheaded the response to level and then complete the win.
After 79 minutes Ronaldinho netted a right-footed free-kick to beat Oswaldo Sanchez - his first international goal since October 2007, when the Selecao hammered Ecuador 5-0.
Only four minutes later, Marcelo finished a combination with Neymar after a long run on the left side.
Honduras beat Jamaica 2-1 in the other friendly as Mario Martinez scored the second-half decider.