Americans not quite ready for primetime

The Costa Ricans took the lead in the 65th minute when Wallace scored on a header off a rebound after goalkeeper Tim Howard stopped a shot. The Maryland-raised defender was playing his first match for Costa Rica.

The Americans came out lively in the opening 20 minutes, but as the match wore on the Americans were drawn into a physical match that featured five yellow cards.

"I want them to go through those kind of down periods in games," Klinsmann said. "We saw here and there players getting tired or a couple minutes where they were struggling. But they need to learn to go through those minutes. They need to fight their way through it. And you saw they got a second breath, a third breath and they did excellent."

The United States had its chances in the second half, the best coming in the 71st minute when Jose Francisco Torres fired a shot that was saved by goalkeeper Keylor Navas.

The United States will return to action September 6 against Belgium in Brussels.

"I think there's no question tonight is going to benefit us," US star Landon Donovan said. "There's a lot to learn from tonight. A lot of our young players will now see you can dominate a team, dominate possession and have the majority of the ball and still lose."