LAS VEGAS— With big games from its three biggest stars, first place came impressively for the United States. LeBron James scored 21 points, Kobe Bryant added 20 and harassed Leandro Barbosa all over the court, and the United States clinched the top spot in its group by beating Brazil 113-76 Sunday night in the FIBA Americas tournament. Carmelo Anthony also had 21 for the Americans (4-0), who for the second straight game pulled away by holding their opponent without a field goal for more than 6 minutes in the second quarter. The Americans improved to 30-0 in Olympic qualifying games and will open second-round play Monday night against Mexico, the fourth-place finisher in Group A, in a matchup of former coaching rivals: Nolan Richardson beat Mike Krzyzewski for the 1994 NCAA title when Arkansas edged Duke. Bryant led the defensive effort that held Barbosa to just four points on 1-of-7 shooting before a Thomas & MackCenter crowd that included former UNLV coach Jerry Tarkanian and NBA Hall of Famer Bill Russell. Injured U.S. star Dwyane Wade watched from the bench for the second straight day. Barbosa entered averaging a tournament-best 27 points after scoring 36 Saturday in a 93-89 victory over the U.S. Virgin Islands. But the Phoenix guard and NBA’s top sixth man never got into this game and was on the bench in foul trouble when the Americans broke open the game late in the second quarter. James, Bryant and Anthony then combined for the first 19 U.S. points in the second half, turning the game into another romp. The Americans came in beating opponents by 52.3 points per game. Brazil nearly beat the United States last year, losing 90-86 in an exhibition game ahead of the world championships. But Barbosa acknowledged that this is a different U.S. team, one that features nine different players this summer. And the Brazilians are lacking one of their key players, Cleveland forward Anderson Varejao, who doesn’t have an NBA contract for next season and opted not to take the risk of playing. Still, the Brazilians kept it close until ending the first half without a field goal after Alex Garcia’s basket with 6:09 remaining. Brazil (3-1) settled for second place in Group B and will face either Panama or Puerto Rico on Monday. The teams with the four best records after second-round play advance to the semifinals next Saturday. The winners of those two games earn spots in Beijing. Brazil trailed only 37-32 with 5:50 remaining in the half before Bryant scored the next three points and James followed with a basket for a 10-point lead. After a Brazil free throw, Bryant and Michael Redd hit 3-pointers in an 8-0 spurt that pushed the U.S. advantage to 50-34 with 2:21 to play. With the game slipping away, Brazil coach Aluisio Ferreira reinserted Barbosa, but he picked up his third foul with 2:21 remaining in the half after trying to stop Bryant on the break. James threw in a runner from beyond 30 feet as time expired, giving the Americans a 57-38 lead. The Americans hit their first five shots and raced to a 12-1 lead a little more than 2 minutes in. Brazil fought back to get within four on Tiago Splitter’s follow with 29 seconds left, and the U.S. was only leading 27-21 going into the second. Splitter, drafted by San Antonio, led Brazil with 13 points. American reserve Tayshaun Prince left the game in the first half after spraining his left ankle while battling for a defensive rebound. He will be re-evaluated today.