England's final World Cup qualifier against Poland could decide whether Sven-Goran Eriksson's team is among the top seeds at next year's tournament.
Fifa told BBC Sport on Monday it is yet to announce how World Cup seedings will be calculated.
If Fifa uses the system employed in the 1998 and 2002 World Cups, England are currently the joint seventh-best seed.
To guarantee top seeding, Eriksson's side need to be in the top eight when the draw is made in December.
The system previously used by Fifa takes into account the average world rankings during the past three years as well as performances at the past three World Cups.
Using those criteria, England are level with France in seventh place with 44 points, two behind Argentina and Italy, but just one ahead of the Netherlands.
Sven-Goran Eriksson's side have slipped to 11th in the world rankings following the dismal 1-0 qualifying loss to Northern Ireland in September.
But they have since beaten Austria 1-0 in Saturday's World Cup qualifier at Old Trafford - and have two matches before the draw for next year's tournament takes place in Leipzig on 9 December.
Matches against Poland on Wednesday and against Argentina in a friendly in Geneva on 12 November will both affect their Fifa world ranking.
Victory in both games will maximise England's chances of keeping among the top eight.
England coach Sven-Goran Eriksson said his side had to win the next matches in case it affected seeding.
"How important Fifa rankings will be, I don't know. We have asked Fifa and they don't know, but it's better to try to win the next two games against Poland and Argentina," he said.
"I still believe we are going to do very well next summer. Of course, it depends on injuries, as with any country. But we will cross our fingers for May and it will be great fun in Germany."
Fifa's system means England are still paying for failing to qualify for the 1994 World Cup finals in the USA.
Ahead of the 2002 World Cup in South Korea and Japan, England were eighth in the seeding list - but were pushed down the list because the two host nations were made top seeds.
World Cup top seeds as of 11 October:
1 Brazil 64 points
2 Spain 50
3 Mexico 48
4 Germany 47
5= Argentina 46
5= Italy 46
7= England 44
7= France 44