Mexico pounced on some dreadful defending to win 2-0 in Guatemala while the United States gave Alexandre Guimaraes an unhappy return to the Costa Rican bench as they trounced the Central Americans 3-0 in Salt Lake City.
Trinidad & Tobago, playing their first competitive international under Dutch coach Leo Beenhakker, beat Panama 2-0 in the other game to move off the bottom of the six-team table.
Mexico, with 10 points from four games, and the U.S., with nine, have already opened up a five-point gap over the rest of the pack and look set to take to of the region's three direct places at the 2006 World Cup.
The battle for the third place, plus the fourth spot which earns a playoff against Asia's fifth team, remains wide open with Guatemala, Trinidad and Costa Rica level on four points and Panama on two.
Guatemala, missing their regular strikeforce of Carlos Ruiz and Dwight Pezzarossi, only troubled the Mexico for the first 20 minutes.
The contest effectively ended when Mexico, missing striker Cuauhtemoc Blanco who pulled out saying he was tired, scored twice in five minutes before halftime.
Brazilian-born midfielder Antonio Naelson put away an easy chance after goalkeeper Ricardo Trigueno failed to cut out a cross and Guatemala defender Pablo Melgar turned Jaime Lozano's cross into his own goal.
"We did everything we had to do, we were intelligent and we had all the clear chances," Mexico coach Ricardo La Volpe said.
UNHAPPY RETURN
Landon Donovan was on target in each half for the U.S. while Brian McBride slammed home a loose ball with three minutes left to make it an unhappy competitive debut for Brazil-born coach Guimaraes.
Guimaraes, who played for Costa Rica at the 1990 World Cup and coached them in Japan and South Korea, was brought back to replace Jorge Luis Pinto, who was fired in March.
Much-travelled Dutchman Beenhakker, who past jobs include Ajax, Feyenood, Real Madrid and the Netherlands, made a good start in the less glamorous surroundings of Port of Spain's Haseley Crawford stadium.
Goals in each half by Coventry City's Stern John and Wrexham defender Dennis Lawrence gave the Soca Warriors their first win in the group.
Trinidad have a much tougher task on Wednesday as they visit Mexico, where Beenhakker has coached local clubs America and Guadalajara.
Panama host the U.S. and Guatemala visit Costa Rica on the same evening.
