The United States boys basketball team ended a disappointing run at the Youth Olympics on Monday by losing to Greece 34-24 in the bronze medal game of a new 3-on-3 format.

The Americans lost to Serbia on Sunday in the semifinals. The Serbs defeated Croatia 22-9 to win the gold medal game.

"We should have won," said Sterling Gibbs, who led the Americans with 15 points. "We just didn't play hard. I don't know why."

The inaugural Youth Olympics in Singapore features the debut of the half-court format in an international, multi-sport competition. Teams play two five-minute periods or until a team scores 33 points. Players must take the ball past the 3-point line after a defensive rebound or made basket.

The International Olympic Committee is debuting several new formats at the Youth Games, including the basketball, a mixed team triathlon relay and mixed swimming relays.

IOC president Jacques Rogge, who watched the basketball competition, has said organizers haven't decided yet whether the new format will be used at the 2016 Summer Games in Rio de Janeiro.

About 3,600 athletes aged 14 to 18 from 204 national Olympic committees are competing in 26 sports at the Youth Olympics from Aug 14-26.

United States boys basketball coach Eric Flannery said the 3-on-3 format requires all players to be skilled dribblers, scorers and defenders.

"Ideally, you would have three guys that were 6-foot-4 to 6-foot-9 that could handle the ball and shoot it, and you have to have guys who can defend everybody," Flannery said. "It's a one-on-one type of game, a lot of isolations."

Brandan Kearney added 10 points for the Americans while Angelo Chol, who was born in Sudan and lives in San Diego, was held scoreless. Theodoros Tsiloulis led the Greeks with 16 points.

The girls team made sure the United States wasn't shut out of basketball medals by defeating Canada 34-16 to win the bronze. Briyona Canty scored 15 points and Kiah Stokes had 10.

"It was tough at first because this is a new game that we're playing competitively," United States girls coach Kathy Richey-Walton said. "There was a lot of trial and error.

"I'm excited that we medaled even though it's not quite what we wanted."

China defeated Australia 33-29 to win the girls gold medal game.