Oh no, ARGENTINA!

Roberto Martinez revealed that Romelu Lukaku is an injury doubt for Belgium's World Cup blockbuster tie against England after the in-form striker picked up an ankle injury on Saturday.

Lukaku and Eden Hazard both netted twice as the Red Devils routed Tunisia 5-2 to leave them top of Group G and on the verge of the last 16.

But the Manchester United forward came off in the second half at the Spartak Stadium in Moscow.

"We need to look at Lukaku's ankle. He took a knock and has to be assessed," said Martinez, who revealed man-of-the-match Eden Hazard also picked up an injury.

"Eden Hazard has a calf knock, Dries Mertens has an ankle problem. There will be major changes against England.

"If we could have seven days to prepare, I'd say we'd start with the same team, but the reality is that you are only as good as the 23 players."

Lukaku's absence would be a blow to Belgium's hopes against England, with top spot in the group likely to be at stake.

The United player already has four goals at Russia 2018 to leave him as joint top scorer alongside Portugal's Cristiano Ronaldo.

However, there was some good news for Belgium boss Martinez, with Chelsea midfielder Hazard expected to be fit to face England in Kaliningrad on Thursday.

"I felt something in my calf in the first half but nothing big and I think I will be OK tomorrow," he said.

Lionel Messi and Luka Modric face off in a mouthwatering World Cup semi-final between Argentina and Croatia on Tuesday, desperate to seize their final chance to win football's ultimate prize.

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 fire Argentina into the final for the second time in eight years against the 2018 runners-up.

Messi, who suffered defeat to Germany in the 2014 final, is desperate to crown an extraordinary career by emulating another Argentine great, the late Diego Maradona, who lifted the trophy in 1986.

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.

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 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, 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 the 1998 World Cup, where they came third.

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

- Croatia defy odds -

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," he said.

"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."

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.

France captain Hugo Lloris said the champions were guarding against complacency and were braced for a pro-Morocco crowd.

"We can only have respect and admiration for what they have done, but nothing happens by chance at this level," he said.

"When a team is capable of beating Belgium, Spain and Portugal, and finish top of their group, it is because they have lots of quality on the field and undoubtedly off it too, in terms of cohesion and team spirit.

"They will be formidable opponents, and on top of that there will be a hostile atmosphere in the stadium."

Demand for the match 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.

Coach Walid Regragui said Morocco were not satisfied with a place in the semi-finals and were hungry for more.

"If you get to the semi-finals and you are not hungry then there is a problem," he said on Tuesday.

"The best team in the tournament, Brazil, is already out. We are an ambitious team and we are hungry but I don't know if that will be enough."

Switzerland hit back with a thunderous strike by Granit Xhaka and a last-minute breakaway goal by Xherdan Shaqiri to claim a famous 2-1 win over Serbia on Friday in a swashbuckling World Cup Group E match tinged with Balkan rivalry.

The Swiss looked in danger of being over-run when Serbia went ahead with an Aleksandar Mitrovic header after five minutes to the delight of their fervent supporters at the Kaliningrad stadium.

Xhaka silenced the Serbian contingent in the 52nd minute, however, when he rifled home a loose ball in spectacular style from 25 metres before Shaqiri ran onto a through ball and finished with aplomb to win the game at the death.

Xhaka and Shaqiri are among several members of the Swiss squad who are of Kosovar heritage, which added an extra dimension to the match.

Serbia refuses to recognise the independence of its former province Kosovo which broke away 10 years ago.

"It's clear that emotions were displayed up and I think we all need to steer away from politics and focus on this sport as a beautiful game that brings people together," Switzerland coach Vladimir Petkovic told reporters.

There was also controversy in the 65th minute when Mitrovic appeared to be held down as he went for a cross but the referee waved play on and there was no video review.

The result left Brazil, 2-0 winners over Costa Rica, top with four points, ahead of Switzerland on goal difference with Serbia on three.

Serbia must beat Brazil in their final game to qualify without relying on the result of the Swiss game against Costa Rica, who are eliminated after losing their first two games.

"This is football, we did not convert some of our chances," Serbia coach Mladen Krstajic said. "Whether this was a penalty or not, I will not comment on that.

"We’re in a situation where we need a win against Brazil on and we will focus and do whatever we can to try and win. Nothing is impossible in life."

FLYING START

Serbia made a flying start and Mitrovic forced Swiss goalkeeper Yann Sommer into an early save with a close-range header.

Sommer was powerless, however, in the fifth minute when Nemanja Matic won the ball and found Dusan Tadic, whose cross was met with a soaring header from Mitrovic.

With Mitrovic proving a handful for the Swiss defence, Serbia threatened to over-run their opponents and missed another chance when a corner flew across the face of goal and Dusko Tosic just failed to make contact.

Switzerland came right back into the game seven minutes after halftime thanks to Xhaka's fulminating strike after a rebound fell nicely into his path.

Xhaka was almost upstaged by Shaqiri who clipped the crossbar with a curling, dipping shot from the unlikeliest of angles and the match turned into a pulsating end-to-end affair which was brilliantly settled by Shaqiri.

Switzerland cleared a Serbia attack and a through pass sent the diminutive forward scuttling away before he slotted the ball neatly into the far corner.

"What is important is that we have developed this winning mentality even when we are down," said Petkovic, whose side have lost only one of their last 24 games.

"We always find a reaction. This is an important characteristic of my team."

Argentina's story in this World Cup has been that of a transformation. From getting handed an unexpected defeat in the opening match against Saudi Arabia to being unbeaten and waltzing through opponents one after another, it feels like we are in for a grand finish! With Argentina running towards their elusive World Cup dream, let us look at the 5 ways Argentina has re-invented them in this world cup.

The worst start acting as the best wakeup call

The Argentine side seemed poised to make a grand entry to this year's World Cup against Saudi Arabia, with the team already up by one goal after half-time, but a second-half spirited display by the Saudis made the unthinkable happen! Argentina got handed the most bitter wakeup call and frankly it set in motion the process of their revamp in this year's competition, having already suffered the worst start, they made sure not to make those mistakes again and with the team playing in the semis, that proved to be the best wakeup call anyone could have asked for!

Captain Messi leading from the front

When was the last time you saw Messi, a player who is universally loved for his gentle persona on and off the field, so charged up and ready to go against anyone for his team? This World Cup we are seeing a different side of Messi, who is less willing to just stand helplessly, and more to lead his team, alone if needed, to get the job done.

From scoring the decisive penalties to getting into a fight with the entire Netherlands team, Messi is on a mission to say goodbye to the World Cup woes of the past, by leading his team to win with exemplary leadership.

Emiliano Martinez, the fiery goalkeeper

Of course, Messi alone cannot do everything for Argentina, he needs help, and he got it in the form of Emil Martinez, their trusted goalkeeper. From giving gritty performances in key matches against Mexico and Australia to the penalty shootout against the intense Dutch side, Martinez has provided the right kind of support to his captain.

When it seemed like Argentina has lost momentum after conceding two late goals, Martinez stepped up in the penalty shootout and saved the first two penalties of the Netherlands. There was not a single Argentine fan in the stands who did not get goosebumps!

Different players stepping up

Messi has all the pressure in the world to deliver for Argentina every time he takes the field, but as football is a team sport, Argentina needed other players to step up, and they did this time. The young Alvarez scoring goals against Australia, Molina's deft finishing against the Netherlands, De Paul acting as the self-described 'bodyguard' of Messi so that he can play his usual game, Lautaro Martinez keeping his calm to score the winning penalty in the shootout — this time the Argentine players are not leaving anything to fate it seems.

Manager with a calming effect

With tensions running high in intense matchups, it is no wonder players are on the edge most of the time. Leading the players this time is the Argentina manager Lionel Scaloni, who has acted as the calming figure of this team. Whenever it seemed like players were losing their tempers or letting the frustrations get the best of them, he stepped in and made sure the shape of the team stays compact and his players focused.