SAN JUAN, Puerto Rico -- Strange things happen at international basketball tournaments, and there were plenty of them -- including Mexico being within five points of the U.S. team in the second half -- on a wacky Wednesday at the Tournament of the Americas.

Mexico, which lost by 74 points to a team of U.S. professionals at the 2001 Goodwill Games, trailed just 52-47 early in the third quarter as the Americans had their sloppiest game of the Olympic qualifying tournament but won 96-69.

Earlier, Venezuela shocked Argentina 97-92, Canada beat the Dominican Republic 78-75 and Puerto Rico locked up a semifinal berth by defeating Brazil 72-70 in three games that featured weird and wild endings.

The most shocking thing about the Mexico-U.S. game was that it didn't become a blowout until the fourth quarter. Mexico led 26-19 after one quarter, surrendered a 13-0 run in the second quarter and never truly had a chance to win in the second half.

Two jumpers by Allen Iverson and a fast-break layup by Jason Kidd highlighted a 10-0 run that gave the Americans a 62-47 lead, and the U.S. team eventually led by as many as 30 points.

"We had some good points in that game and some bad points," Iverson said. "We played good enough to win, that's the most important thing."

Venezuela came up with several key steals in the final minutes and closed the game with an 18-2 run to hand Argentina its third loss of the tournament.

Barring a victory by Puerto Rico over the U.S. team in the final game of the second round, Argentina needs to defeat the Dominican Republic on Thursday to avoid a semifinal matchup with the United States on Saturday, when two of the three available berths in the Athens Olympics will be earned. A third berth will be awarded to the team that wins the third-place game Sunday.

Canada is assured of finishing no lower than third, thanks in part to a major mistake by the Dominicans with 4.4 seconds left.

With Canada leading 76-75, Franklin Western of the Dominican team went to the line for two free throws as no one from his team lined up along the lane to get a possible rebound. Western missed both shots, Steve Nash made two free throws with 1.2 seconds left, and the Dominicans missed a 3-point attempt from beyond midcourt at the final buzzer.

"I was surprised when they didn't have a guy there," Canada coach Jay Triano said.

Nash had nine points and eight assists for Canada, which was led by Denham Brown's 16 points.

The end of the Venezuela-Argentina was bizarre, too.

Argentina was ahead 90-79 with 3½ minutes left before Carlos Morris scored seven straight points and Argentina had four straight possessions in which it could not get the ball past midcourt.

Two free throws by Oscar Torres with 59 seconds left gave Venezuela a 93-92 lead.

After another basket by Venezuela, Argentina had a chance to tie it but Manu Ginobili's 3-point attempt got wedged between the rim and backboard, resulting in a jump ball situation. A recent rule change has eliminated all jump balls except at the beginning of the first and third quarters, and the possession arrow was pointing Venezuela's way. Victor Diaz was fouled with 3.7 seconds left and made two free throws for the final margin.

"It looked terrible. We didn't even have a hint of clarity," Ginobili said.

In the Brazil-Puerto Rico game, Marcelo Machado of Brazil tied it at 70 on a 3-pointer with 1:15 left, and Eddie Casiano of Puerto Rico drove through traffic for a layup with 19 seconds left. Valter Silva passed up an open 3-pointer for Brazil and threw a pass that was deflected out of bounds with 1.9 seconds remaining. Brazil inbounded to Anderson Varajao, whose off-balance 3-pointer missed everything as the final buzzer sounded and a sellout crowd celebrated wildly.

Puerto Rico's leading 3-point shooter, Elias Ayuso, said he had reached agreement with the NBA champion San Antonio Spurs on a one-year contract.

Ayuso, a shooting guard who has made 18 3-pointers in Puerto Rico's seven games, led Puerto Rico with 19 points.

"I was very excited to get this opportunity," Ayuso said. "(Spurs coach Gregg) Popovich was the one who liked me from the beginning."

The top two highlights of the Mexico-U.S. game came in the second quarter, with Vince Carter responsible for both.

First, Carter soared high in the air under the basket and blocked a shot by plucking it out of the air. Carter reacted as though he expected goaltending to be called, but the referees let play continue.

Carter then threw down a vicious, two-handed tomahawk dunk off a pass from Kidd to complete the 13-0 run that gave the Americans a 45-33 lead.

Tim Duncan led the U.S. team with 16 points.