No plan survives first contact with the opposition. Argentina's pulsating 1-1 draw with Paraguay on Wednesday was a battle between two sides who had run headlong into this problem in their opening matches.

Argentina's caretaker coach Lionel Scaloni was full of bold talk when he was appointed last August.

"I've always liked more direct, vertical football," Scaloni said then. "Winning the ball to arrive at the opposing goal as quickly as possible."

And so he went about building his side with two wingers and quick transitions to the flanks, the ball played rapidly into space. Then Lionel Messi returned from his international hiatus and, of course, wanted the ball played to his feet. Argentina's debut match, a 2-0 defeat to Colombia, was marked by enormous confusion. The half-time substitution of left winger Angel Di Maria by the entirely right-footed Rodrigo De Paul was the moment that Scaloni's initial idea bit the dust. And so, searching in the dark for something new, something coherent, he changed the formation against Paraguay to something like a 4-4-2.

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Paraguay coach Eduardo Berizzo, meanwhile, also announced his own revolution on his appointment in February.

"I'm always thinking of how to dominate the game," said the ex-assistant of the king of the high press Marcelo Bielsa. "I don't want to be dominated, sit back and try to scrape results."

But the historic identity of Paraguay is exactly that -- a team who over the years have revelled in deep defence. Berizzo's first attempt to play higher up the pitch in a competitive match was not a conspicuous success. On Sunday, they were flattered by the 2-0 lead they opened up against Qatar, and may even have been flattered by the final scoreline of 2-2. If Qatar stretched them out and played through them, what would Argentina and Messi do?

Berizzo chose not to run the risk. It was back to basics in Belo Horizonte for Paraguay. The order of the evening was deep defence and counter-attack.

This had pros and cons. The big pro for Paraguay is that, in a low-scoring game like football, defending is the easier part. Two teams were trying to improvise a solution, and it was more comfortable for Paraguay to destroy than it was for Argentina to construct. The other pro, specific for this game, is the lack of pace in the Argentina back line -- a problem that has dogged La Albiceleste for years.

In the break he made to set up the Paraguay goal, Miguel Almiron was faster running with the ball than the rival defenders were running without it. Paraguay should have won the game when they exposed this flaw a second time. Caught on the wrong side, Nicolas Otamendi committed a desperate foul in the area, only for Derlis Gonzalez to waste the penalty with a weak shot, pushed around the post by Franco Armani.

By this time, Argentina had drawn level from the spot -- a moment that illustrated the risks of the Paraguayan approach. Argentina lacked organisation, but defending deep can always run into the problem of conceding set pieces close to goal -- a risk much heightened by the appearance in the game of the video assistant referee.

The decision to penalise Ivan Piris for a hand ball in the box is controversial. It did not look clear even after studying the video evidence. Without VAR, the supposed offence would have gone unnoticed and Argentina would have been happy to go ahead with the corner that Messi was about to take when the referee held his arm aloft and began the long conversation with his colleagues.

Perhaps Argentina got lucky. But they had to change once more to earn their luck. Scaloni's experiment with Roberto Pereyra as a central midfielder was a clear and predictable failure, abandoned at half-time. On came Sergio Aguero, giving more options closer to goal, and Aguero was key to the move where Argentina won their penalty.

With Aguero up front, De Paul on the right of the midfield trio and Giovani Lo Celso on the left, the balance was a little better. Space started to open up for Messi to run at the Paraguay defence, and Argentina are still alive in the competition.

In a World Cup, one point from two games would be a disaster. The Copa America is more lenient. Two of the third-placed teams go through to the quarterfinals. In the history of the 12-team Copa, four points has always been enough to make it through, so a win against Qatar on Sunday should be enough for Argentina.

Scaloni, then, has a few days to sit down with his players and come up with the game plan that will not crumble on first contact with the Asian champions.