Mexico kept the game respectable into the second half on Monday before the US pulled away for a 127-100 victory in the second round of the FIBA Americas tourney.
In other games, Puerto Rico downed Brazil 97-75, Argentina routed Venezuela 86-63 and Canada outmuscled Uruguay 95-88.
Carmelo Anthony scored 28 points, tying the US record in an Olympic qualifier. He had 16 in a sensational opening quarter, when the US shot 80 percent.
The Mexicans, who sneaked into the second round through a three-team tiebreaker, outplayed their more fancied counterparts for much of the next two periods before the US put them away for good late in the third.
Kobe Bryant added 21 points and LeBron James and Dwight Howard had 19 apiece for the US, which led by only 15 points midway through the third quarter after beating its first four opponents by 48.4 points per game.
The US were scheduled to face Puerto Rico last night.
Mexico rarely showed the pressure defensive style that Richardson used at Arkansas, but hustled for offensive rebounds and shot 15-of-28 from 3-point range to hang around in the game.
Romel Beck, who played for the University of Nevada, Las Vegas, scored 20 points for Mexico.
Earlier, Larry Ayuso had 24 points for Puerto Rico, the last team to advance to the second round of the tournament that decides two berths in the Beijing Olympics.
Puerto Rico made a statement by dominating all but the third quarter in the win over Brazil.
Brazil got within 62-54 with 21 seconds left in the third quarter,but Puerto Rico went on a 19-2 run for an 81-56 lead with 4:30 to play and cruised from there.
Peter John Ramos and Filiberto Rivera both had 14 points for Puerto Rico and Carlos Arroyo finished with 11.
Barbosa finished with 34 points, 26 in the second half, on 10-for-20 shooting and was 12-for-13 from the free throw line.
Carlos Delfino had 19 points and 11 rebounds and Argentina hit 14 3-pointers in the win over Venezuela.
Roman Gonzalez had 21 points on 9-of-11 shooting to lead Argentina, which finished the first round as the only other unbeaten side other than the US.
Delfino made three 3-pointers in the first half as Argentina took a 51-34 lead and coasted to the win.
Canada got physical with Uruguay and used its size advantage to lead for the entire game. Jesse Young had 22 points, Levon Kendall had nine points and nine rebounds and Samuel Dalembert had 10 points, five rebounds and three blocks to lead Canada.
Young, who had a total of 29 points in Canada's four opening-round games, was 10-for-16 from the field. But it was on the defensive end where he and his teammates were even more impressive.
Uruguay's Esteban Batista finished with 16 points on 6-for-15 shooting and had six rebounds.