As qualifying for the 2018 World Cup reaches its climax, Lionel Messi's Argentina finds itself in trouble, Syria faces a play-off to keep its remarkable dream alive and European champion Portugal has work to do.

AFP Sport looks at the state of play in each of the regions:

Argentina in danger

Brazil secured its place in next year's finals back in March, but three automatic berths remain up for grabs in South America ahead of the final two rounds of qualifying matches. Two-time World Cup champion Argentina hasn't missed the tournament since 1970, but five-time Ballon d'Or winner Messi and his compatriots, runners-up in Brazil three years ago, are currently languishing in fifth place.


Messi brace seals points at empty Camp Nou

While that would not spell the end of the road for Argentina, instead sending it into a two-legged play-off against New Zealand, even that is far from assured with Copa America holder Chile lurking just a point behind in sixth.

Germany cruising, France on thin ice

Europe will provide 14 of the 32 competing teams in Russia, the hosts included. But so far only Belgium has punched its ticket to the finals going into the last two sets of fixtures.

Pique whistled at Spain open training session

World champion Germany, which needs just a draw in Northern Ireland on Thursday, leads a handful of other sides which can wrap up qualification this week.

England is five points clear in Group F, while Serbia is in control of its section and 2010 champion Spain has the edge over Italy in their two-horse race.

Navas defends Ronaldo amid goal drought

The nine group winners progress automatically, while all but one of the runners-up advance to the play-off round to determine the final four qualifiers.

'Worst experience of my career'

Portugal, while sure of at least making the play-offs, face a critical final match at home to Switzerland as Cristiano Ronaldo and his team-mates look to overturn a three-point deficit in Group B.

Carvajal, Morata and Iniesta ruled out of World Cup qualifiers

France holds a tentative one-point cushion over Sweden in Group A and will be all too aware of the dangers posed by a trip to Bulgaria, the country responsible for its absence at the 1994 World Cup.

Nigeria and Tunisia within sight

Five places are on offer in Africa, but none as yet have been claimed. Nigeria is closing in on a sixth World Cup appearance, with reigning continental champion Cameroon and Algeria out of the running in a challenging section, but Zambia could still deny the Super Eagles.

Tunisia is well positioned to end a 12-year World Cup exile, leading nearest rival the Democratic Republic of Congo by three points, while Egypt is in control of its destiny.

But other groups remain wide open with just the first-place finishers qualifying for Russia. Ivory Coast top Group C on seven points, but both Morocco (six) and Gabon (five) still harbour genuine hopes.

It is a similar situation in Group D after FIFA's decision to annul South Africa's 2-1 win over Senegal from November 2016 -- a match manipulated by a Ghanaian referee. Burkina Faso and Cape Verde head the pool on six points, but Senegal trails by just a point with its match against Bafana Bafana to be replayed in November.

War-torn Syria head into play-offs

Iran, Japan, South Korea and Saudi Arabia will represent Asia in Russia next year, but Syria and Australia will attempt to join them via the play-offs.

Syria prolonged its fairytale World Cup campaign with a dramatic stoppage-time equaliser in its final group match to set up a double-header against Australia on October 5 and 10.

The Socceroos are bidding for a fourth straight finals appearance while Syria, which has never reached the World Cup before, has kept its dream alive despite the brutal civil war that has forced it to play all its home games abroad.

It will take on Australia in Malaysia in the first leg before travelling to Sydney for the return. The winner of the tie will meet the fourth-placed team from CONCACAF with a spot in Russia at stake.

Mexico and who else?

Mexico will compete at its seventh straight World Cup next summer, with Costa Rica also on the verge of direct qualification. But a third automatic berth is still in play, while the fourth-placed side can also qualify through the inter-continental play-offs.

Panama, in third, leads the United States and Honduras by a single point with two rounds of games still to play.