England and Belgium are both through to the round of 16, but if they play to a draw in their finale, they'll go way down the tiebreakers line to see who finishes in first.
England powered its way to an impressive 6-1 win over Panama on Sunday, booking their place in the last 16 of the competition with a game to spare.
A Harry Kane hat trick, combined with a John Stones brace and a Jesse Lingard wonder goal ensured the Three Lions' win, but there's still work to do if they are to top Group G.
Of course, with a win over Belgium on Thursday England will top the group, but with both teams currently level on points and goal difference, a draw will make things awfully complicated.
If it is indeed a tie, here is exactly how FIFA will be working out who will awarded the top spot in the group:
The number of points is the first port of call, but as it's a draw, that will obviously of no use. Next is goal difference, again, as the teams are level in that respect two, there's no splitting them. Number of goals scored in all group matches is next - that's currently 8-8, so there's still no deciding factor! The next category - points against each other - is equally as useless.
The fifth category, goal difference between the two sides, would again be of no use in a draw, as would the sixth - category goals scored between the two sides. Finally, then, it will come down to fair play points (meaning bookings and red cards, and England is currently winning this).
If this winds up being a draw, then it will all come down to names being drawn out the hat.
England will head into their final group game brimming with confidence, after dispatching Panama with ease.
While a win was always on the cards, the energy and attacking threat posed by Gareth Southgate's side will have done a lot to win over even the staunchest of England critics, with a record breaking win lifting the spirits of the nation.
However, Belgium are likely to give England a difficult evening, having also impressed in the group stage thus far. Eden Hazard and Romelu Lukaku were in scintillating form against Tunisia, as they powered to a 5-2 win, and the sheer wealth of talent in Roberto Martinez's side will provide a real test of England's quality. Martinez has hinted that he'll be resting a number of his stars, either those on yellow cards or those nursing slight knocks.
Of course, second in the group could wind up being more desirable depending on how the other groups unfold and the bracket shapes up. England and Belgium will have the benefit of playing on the final day of the group stage, so they'll know just where a team like Germany or Brazil winds up after their results (should they advance).