Playing defensive and closing spaces is the only chance for Argentina, leaving Messi and another attacker (preferably Kun) to do something in the offensive part. It's a negative approach, I know, but you have to be pragmatic here. Leaving spaces behind is a suicide against France, but they can find problems against a good defensive system.
They did it in WC'90 against Brazil, with that action of Maradona with Caniggia in the last minutes after defending the whole game. And it was a miracle.
They need another miracle on Saturday. But miracles can happen when you have God in your side.
This is like a final for Argentina, if they win this they will go far... not because the rest of their path is easier but because how much room they have for improvement with the time and confidence they get with winning this one.