I think the Argentina - Croatia game is really likely to end up with penalties. Croatia seem to have the strength to have another similar game to the Brazil one. Brazil were also a very powerful attacking team but they had big problems on dealing with Croatia defense and their goalkeeper at the same time. Livakovic was even the man of the match.
Argentina will need to play a very effective game in attacking. They need to be as precise as possible to break the lock of the game early. The more time they don't get ahead the better for Croatia to keep the game balanced.
This may be Messi's last chance to do something good for his team. We all expect Messi to play at his best today. Besides, it is very important for Argentina today, because the best player in the world like Messi needs to win the World Cup. Hope all players of Argentina team will play responsibly and ensure victory.
Every player has a dream to be the world champion - as someone mentioned it below it this is the last chance for Messi to do something good for his team. But then again he is a human to his strength too - we have so much expectation from Messi - Ronaldo - Neymar.
And we want them to show some superman skills in every match they play!