Croatia's midfielder Luka Modric trains with the team at the Luzhniki Stadium in Moscow, Russia on Tuesday. Photo: AFP

Croatia's run to the World Cup final is largely down to Luka Modric's tireless work in midfield but their ability to switch tactics efficiently should be a warning for opponents France on Sunday.

When the two sides meet at Moscow's Luzhniki Stadium all eyes will be on Modric and how the French will attempt to put shackles on the creative midfielder, who at 32 is eyeing the biggest prize of the sport.

While Modric may be a worthy contender for Footballer of the Year, his team's quick switch in tactics during their World Cup semifinal against England shows that danger lurks around every corner playing against this Croatia squad.

The English were already with one foot in the final after leading 1-0 and completely dominating the game, with Modric and fellow midfielder Ivan Rakitic, who have five Champions League titles between them, unable to feed their forwards.

But after the break, a quick switch from their favored 4-3-3 to a 4-1-4-1 meant that suddenly the game moved higher up the England half and the wings became Croatia's main points of attack.

Sime Vrsaljko is not your average right back. At times he operates as a world-class winger whose power, accuracy in crosses and passes have little to do with that of a full-time defender.

When Modric is bogged down in midfield, it is Vrsaljko who will often shoulder the duty of carrying the ball past the midfield and it was one of his forays into the English half that allowed him to cross for Ivan Perisic to level.

The same goes for the other wing, with Ivan Strinic equally attack-minded and his replacement late in the game, Josip Pivaric, doing as he was told, crossing into the box from the left to give Mario Mandzukic the chance to score the winner and send his team into the final.

With opponents' defenders kept busy with trying to contain the three strikers and the holding midfielders working to deal with Modric and Rakitic, it is the fullbacks who could prove to be key.

With a strike force that is the envy of almost every other World Cup team, with players such as Mandzukic, Perisic, Ante Rebic and Andrej Kramaric, Croatia can be lethal.

But they can equally turn into a hard-working defensive mechanism as they showed when Russia pressed high in their quarter-final stopping from unfolding their attacking game plans.

France will obviously need to use N'Golo Kante's and Paul Pogba's power and stamina to rein in Modric and Rakitic early but their defense must also be equally alert to the danger from the wings if they are to shut out the Croats and lift their second World Cup.