As unlikely as it may seem given the resumes of the two nations involved, including the seven combined world championships, Argentina and Brazil had never reached the semifinals in the same World Cup until this year. (Complete coverage of FIFA World Cup 2014)
With a 1-0 victory over Belgium on Saturday, thanks to a goal by Gonzalo Higuain, Argentina joined Brazil, which beat Colombia on Friday, in the final four. The possibility exists that the two teams, South American giants and bitter rivals, could face off in the final in Rio de Janeiro, which many feel would provide the most fitting conclusion to this World Cup. (Also read: Messi encouraged by Argentina's 'best match')
Argentina, the winner in 1978 and 1986, is back in the semifinals for the first time since 1990, when a rough group coming off a title relied heavily on the skills of Diego Maradona and Claudio Caniggia, who did just enough to win, before losing to Germany in a desultory final.
Twenty-four years later, Argentina still relies heavily on two stars - these days, they are Lionel Messi and Angel di Maria - but di Maria's status for the team's next game is uncertain; he left Saturday's game with a right thigh injury.
Messi has been indispensable to Argentina, bailing the team out of several precarious situations either by scoring himself or by sending passes that have led directly to goals. (Match highlights)
"He is water in the desert," said Alejandro Sabella, Argentina's coach.
The players surrounding Messi, with less skill and less of an ability to dictate the flow of play, make Argentina look rather pedestrian, at least in the eyes of one vanquished opponent.
"We are not impressed by Argentina," said Marc Wilmots, Belgium's coach. "Definitely not. It is just an ordinary team."
But Argentina found production from sources other than Messi on Saturday. Higuain, who has been under pressure for his lack of goals, silenced his critics with a decisive strike in the eighth minute, and Argentina's stout defense made it difficult for Belgium to create scoring chances.
With thousands of fans singing and chanting for Argentina, the team rode theÂ wave of support in what felt like a home game.
The Belgians, who had required extra time to beat the United States in the previous round, had a flurry of attempts on goal in the closing minutes but were unable to convert.
Argentina will play the Netherlands, which defeated Costa Rica later Saturday afternoon. With Brazil playing Germany in the other semifinal, the final four will feature international soccer powerhouses, with 10 World Cup championships among them, regardless of that result.
The primary concern for Argentina, though, is the status of di Maria, who left the game midway through the first half. If di Maria is sidelined, Argentina may have to rely even more on Messi.
Belgium, meanwhile, got very little production from its star playmaker Eden Hazard, who was taken off in the second half.
Higuain scored the game's lone goal with a perfect one-time strike from 17 yards out in the eighth minute. The play started when Vincent Kompany, Belgium's normally reliable central defender, lost the ball in his own half.
Messi made a few slick moves, spinning free from three defenders in the middle of the field, before distributing the ball wide to di Maria. Di Maria's pass into the box was deflected by Jan Vertonghen and went straight to Higuain, as if on a tee. He struck the ball perfectly with the laces of his cleat, a clean power shot to the far corner of the net that gave Belgium's goalkeeper, Thibaut Courtois, had no chance.
Despite the mounting pressure back home, Higuain said that he was not anxious about scoring and that he knew his time would come.
"The striker wants a goal," he said, "and what is better than doing it today?"
Argentina secured the slim lead by playing behind the ball and closing down any chances. Even when Belgium brought on Romelu Lukaku, who proved so effective against the United States, it could not find a way to tie the score.
"After 24 years, this is a good tribute for this squad," Sabella said, adding that his team would "go down in history as one of the best four in the world."
"Maybe we can take it further," he said.
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