LONDON » When the moment arrived, the Americans responded.

They’re still unbeaten, but no longer untested.

Pushed to the max by a fearless Lithuanian team smelling a world-shaking Olympic upset, the U.S. collection of basketball superstars united as one.

And LeBron James led the way.

Two days after running and gunning to a record-shattering 83-point win, the U.S. was forced to play a possession-for-possession game in the fourth quarter in a 99-94 win over Lithuania.

The Americans were in serious trouble until James stepped up in the closing minutes.

"It was like LeBron said, ‘I got this, I’m doing this,’ " U.S. coach Mike Krzyzewski said.

James scored nine of his 20 points in the final 4 minutes for the U.S. (4-0), which had looked invincible in thrashing Nigeria 156-73 on Thursday. But the Americans were reminded that the path to a gold medal is loaded with traps, and Lithuania nearly sprang one.

"You want to get tested," James said. "We love the competition. We’ve got some of the greatest competitors in our league, in this world, so you want to have a game where you feel like you were tested, and we had that today."

And then some.

The U.S. trailed by two points with less than 6 minutes left before using a 15-4 run to put away Lithuania (1-3), which was seeking to duplicate its stunning win over the Americans in 2004 win at Athens.

Carmelo Anthony also had 20 points for the U.S.

Linas Kleiza scored 25 points and Martynas Pocius, who played for Krzyzewski at Duke, had 14 for Lithuania.