Tuesday 8 November 2016 17:13, UK
World Cup qualifying resumes this week, with the race to reach Russia 2018 gathering pace.
England and Scotland meet in a mouth-watering match-up at Wembley on Friday, but across the globe nations are vying for a World Cup spot.
Here, we run through the qualification state of play, to see which countries are on course and which teams have work to do, starting with the home nations and the Republic of Ireland...
Group C
In Group C, Northern Ireland are third, five points behind leaders Germany.
Michael O'Neill's men take on second-placed Azerbaijan on Friday, knowing victory would move them level on points with the visitors to Windsor Park.
With a key fixture against fourth-placed Norway coming up in March, before a trip to Azerbaijan in June, victory this week could provide a launchpad for Northern Ireland.
Group D
In Group D, Republic of Ireland are tied on points with early leaders Serbia, while Wales, on the back of their Euro 2016 heroics, are two points behind in third.
Both Ireland and Wales face tough tests this month. Martin O'Neill's side head to Austria for a clash with the talent-filled fourth-placed nation, while Chris Coleman's Wales host Serbia in Cardiff.
Ireland and Wales meet in Dublin in March, so capturing a big scalp this Saturday would be a significant boost.
Group F
England v Scotland is the headline clash in Group F this week, with the hotly anticipated 'derby' at Wembley as much about bragging rights as World Cup qualifying points.
However, Gordon Strachan's men are more in need of a win than their hosts, having stuttered to a draw against Lithuania and defeat to Slovakia last time out, after opening their campaign with a 5-1 victory in Malta.
England were held in Slovenia after seeing off Malta in October so will not be able to replicate their 100 per cent qualifying record for Euro 2016, but nonetheless they are still well placed at the summit.
Cause for concern?
It's still early days in qualifying, with just three games played, but Netherlands - after their failure to reach Euro 2016 - are currently third in a tough Group A.
Major tournament regulars Czech Republic have also made a slow start in Northern Ireland's group, while Austria (Group D), Romania (Group E) and Turkey (Group I) all have ground to make up.
However, Iceland - fresh from their breakout performance at Euro 2016 - are riding high, joint-top of Group I, while Spain and Italy are where you'd expect them to be in Group G.
Euro 2016 finalists France lead the way in Group A, while their conquers Portugal continue to recover from an opening round loss to Switzerland in Group B.
Click here to see all of the UEFA World Cup Qualifying groups
Qualification for the 2018 World Cup is a convoluted affair, but the process is well under way in other regions.
In Asia, two pools of six are led by Iran and Uzbekistan and Saudi Arabia and Australia after four games, with South Korea and Japan currently on course for a play-off. The winner would then face a fourth-placed team from Central and Northern America.
Currently the CONCACAF qualification process is still at a preliminary stage but USA, Costa Rica and Mexico are well placed to progress to the next phase.
Meanwhile, in South America, Argentina have work to do. They are currently sixth in the CONMEBOL 10-team table - and out of the qualification places.
They are level on points with fifth-placed Chile, who are currently set for a play-off with the top team in Oceania (most likely New Zealand).
With eight games to play, Argentina face Brazil this week and cannot afford many more slip-ups. Their rivals are top of the table and well on course for Russia 2018, with Uruguay, Ecuador and Colombia also currently in the qualifying spots.
Meanwhile, in Africa, the third and final qualification stage is just one game old. 20 teams have been split into five groups, with the winner of each pool qualifying for the finals.
