Croatia and Argentina face each other on Tuesday at the Lusail Stadium with a place in the World Cup final at stake.
AFP Sport looks at some of the keys to the game.
Messi or Modric magic?
The late-career evolution of Lionel Messi into a clever creator operating behind the front line has intensified at this World Cup.
He illustrated just how effective he can be with his superb defence-splitting pass to set up the opening goal in the quarter-final against the Netherlands.
Croatia are unlikely to put a specific man-marker on Messi, relying on what has been a solid defence and one of the best midfields in the tournament to gain the upper hand.
Marcelo Brozovic occupies the deepest defensive role in the Croat midfield trio and is likely to have the most work to do in nullifying Messi, 35, but Mateo Kovacic put in a strong defensive shift against Brazil and is likely to be asked for a repeat performance. Read more