Argentina and Lionel Messi face Croatia on Tuesday in a World Cup semi-final that pits South American flair against the guile of Luka Modric and a remarkable fighting spirit.

In the second semi-final on Wednesday, reigning champions France take on giant-killing Morocco, the first African team ever to reach the last four of a World Cup.

But first all eyes will be on the cavernous Lusail Stadium, where Messi, now 35, will attempt to guide Argentina into the final for the second time in eight years against the beaten finalists in 2018.

Messi, who suffered defeat to Germany in the 2014 final, is desperate to crown an extraordinary career by finally winning the World Cup and emulating another Argentinian legend, the late Diego Maradona.

The Paris Saint-Germain forward was a pivotal figure in Friday's stormy quarter-final win over the Netherlands, when a record 18 yellow cards were shown and players from both sides were involved in a melee as the referee fought to regain control.

The match ended with Argentina players appearing to taunt their distraught Dutch opponents before sprinting away to celebrate after a penalty shoot-out win.

Even the normally mild-mannered Messi was caught up in the bad blood, shouting abuse at Dutch players while he was being interviewed after the game.

Argentina coach Lionel Scaloni defended his players' conduct in an eve-of-game news conference on Monday, insisting they had nothing to apologise for.

"The game the other day was played in the right way by both teams. That is football," said the 44-year-old Argentina coach.

"I don't buy this idea that we don't know how to win. The game was played in the right way."

CROATIA SURPRISING AGAIN 

Croatia, who beat Japan and pre-tournament favourites Brazil in penalty shoot-outs to reach the last four, have not won a knockout game in normal time at a major tournament since they came third at the 1998 World Cup.

Despite doing it the hard way, the country of 3.9 million people surprised the football world by reaching the final four years ago, where France crushed their dreams with a 4-2 win.

Croatia, with Real Madrid playmaker Modric still the leader on the pitch at the age of 37, have again defied the odds to stand on the brink of a second successive final.

Coach Zlatko Dalic said he wanted Tuesday's match to be remembered as the "greatest game" in the country's history.

"At back-to-back World Cups to be among the four best national teams, that's an extraordinary success for Croatia," said Dalic.

"However, we want more," he added. "I'm optimistic and have full confidence in my players. They've shown their great quality and strength of character, and deserve to be in the final."

Dalic said a lack of energy in Qatar, despite the marathon games in the last two rounds, would not be an obstacle.

"We are still strong, with energy and enthusiasm, without a doubt," he said. "We are going to give it our all, just as we have done in previous games.

"Against Argentina we will do the same, we will give our all. We don't have any injury problems. They don't feel tired."

Caught the imagination 

France are strong favourites to beat Morocco and take a step closer to defending their title on Wednesday.

But the African team's history-making run to the semis has caught the imagination of a continent and they have been backed by legions of fans in Qatar.

The match will have added spice -- France was Morocco's colonial power and hundreds of thousands of people with Moroccan roots live and work in the country.

Demand has been so great that Royal Air Maroc has announced it is laying on 30 extra return flights to take euphoric fans to the Gulf state.

France defender Raphael Varane has insisted that there would be no complacency from the World Cup holders.

"We know Morocco are not here by chance," he said. "It is up to us experienced players to make sure everyone is prepared for another battle."

One man who knows about winning World Cups, Brazilian star Ronaldo, said he believed France would go on to take back-to-back global crowns.

Ronaldo, who scored both goals as his country won the 2002 World Cup final against Germany, told a media roundtable that included AFP: "France, match after match, are backing up their status as favourites and I still see them as the big favourites."