Here’s a look at some of the keys to the game:
PUT THE ‘ CREAM ‘
Lionel Messi’s late career evolution into an intelligent creator working behind the front line has intensified in this World Cup.
He illustrated how effective he can be with his superb pass splitting the defense to set up the opening goal in the quarter-final against the Netherlands.
Croatia are unlikely to put a specific goalscorer on Messi, relying on what has been solid defense and one of the best midfielders in the tournament to gain the upper hand.
Marcelo Brozovic occupies the deepest defensive role in the Croatian midfield trio and is likely to have more work to do to undo Messi, 35, but Mateo Kovacic made a strong defensive shift against Brazil and is likely to be asked to repeat the performance.
MODRIC – THE MASTER OF THE MIDFIELD
With the ball, Croatia have their little veteran master in 37-year-old Luka Modric, whose ability to dictate pace, maintain possession and take his team into danger zones is central to his country’s hopes of reaching successive finals in World Cup.
OVER 90 MINUTES
Just like four years ago in Russia, where Croatia won all their knockout matches after extra time – twice on penalties – before the final, Zlatko Dalic’s side showed a remarkable ability to grind out results beyond 90 minutes.
Croatia conceded the opener against both Japan and Brazil but came back to force the match to penalties and win.
Will that impressive mental strength prove decisive again, or will those protracted battles take a physical toll?
It will help Croatia that Argentina also had to go to penalties in their emotionally draining quarter-final victory over the Netherlands, and a crucial factor on Tuesday will be which side are fresher for the task.
THE SEA OF BLUE AND WHITE
If there’s one area where Argentina have a clear advantage, it’s in the stands, where more than 40,000 Argentine fans clamored for their team at the Lusail stadium against the Dutch.
Such was the atmosphere that the quarter-final fixture effectively turned into a home match for Argentina, with only a smattering of orange-clad supporters in the stadium, which has a capacity of nearly 89,000.
It will almost certainly be the same story, in the same stadium on Tuesday, with the much smaller group of Croatian fans drowned out by the chants and chants of the Argentine faithful.
Will this impact the game? Almost certainly. Numerous studies have shown that playing in front of a supportive crowd has a positive impact on performance.
With Messi in a deeper role, Argentina are in the unusual position of not having an established world-class striker and this is also the case with Croatia.
Dalic started the semi-final against Brazil with Andrej Kramaric at centre-forward before Bruno Petkovic replaced him and scored the decisive equaliser.
Against the Dutch, Argentina started Manchester City’s Julian Alvarez as main striker with Inter Milan’s Lautaro Martinez replacing him and causing a lot of trouble in extra time.
It will be interesting to see if either of these substitutes are given the start in the semi-finals or again asked to make an impact off the bench.