Ottawa:Maximiliano Moralez scored the lone goal in first-half injury time Sunday night and Argentina kept alive its bid for a second consecutive title at the Under-20 World Cup with a 1-0 quarterfinal victory over Mexico.
It was Argentina's second victory over Mexico in an international competition in five days after the senior side beat El Tri 3-0 in the semifinals of the Copa America on Wednesday.
The 1.60-metre Moralez scored the biggest goal of the tournament for his country so far. His shot from the top of the penalty area took a deflection off a defender and wrong-footed Mexico goalkeeper Alfonso Blanco just before halftime in an entertaining match played before a capacity crowd of 26,500.
Argentina moved a step closer to adding to its record five titles at the tournament, although it wasn't easy against a Mexican side that was in part formed from the team that won the U17 World Cup in 2005.
Argentina, which has allowed only one goal in five games, next faces Chile in the semifinals on Thursday at Toronto's BMO Field after the Chileans beat Nigeria 4-0 in extra time earlier Sunday at Montreal.
Austria and the Czech Republic face off Wednesday in Edmonton in the other semifinal.
Sunday's match was the only one of four quarterfinals that did not go to extra time or penalties.
Argentina played its group-stage games in Ottawa and enjoyed tremendous crowd support, however, fans turned out in equal support for the Mexicans on Sunday. It made for a loud and lively atmosphere of whistling, drumming and chanting in the stadium.
Both teams were in an attacking mood from the kickoff and Argentina's Angel Di Maria, starting at forward in place of Mauro Zarate, tested Blanco with a drive that the keeper tipped over the bar.
Blanco was pressed into action again on the ensuing corner, blocking a header from close range.
At the other end, Carlos Vela tested Argentine keeper Sergio Romero in the 13th minute. Mexico's appeal for a handball in the box was ignored by Spanish referee Alberto Undiano Mallenco when a cross appeared to make contact with a defender's arm. Moments after that, Vela swivelled on a ball at the top of the box and unleashed a volley that beat Romero only to strike the post.
Moralez finally made the breakthrough with virtually the final kick of the half.
A minute into stoppage time, the tiny winger took a pass from Di Maria at the top of the 18-yard box and let fly with a shot that changed directions off the thigh of a Mexican defender and sent Blanco going the wrong way.