There are two questions still to be resolved when South America plays its final round of World Cup qualifiers this Wednesday.
Firstly, who finishes fifth and goes on to meet Australia in the play-off?
SOUTH AMERICAN STANDINGS
1 Argentina Pld 17 Pts 34
2 Brazil Pld 17 Pts 31
3 Paraguay Pld 17 Pts 28
4 Ecuador Pld 17 Pts 27
Top four qualify for World Cup
5 Uruguay Pld 17 Pts 22
6 Colombia Pld 17 Pts 21
7 Chile Pld 17 Pts 21
8 Venezuela Pld 17 Pts 18
9 Peru Pld 17 Pts 15
10 Bolivia Pld 17 Pts 14
Fifth team faces play-off with Oceania winners Australia
Three teams are in contention - Uruguay, Colombia or Chile.
And there is a secondary question. Who finishes top of the group?
It is worth nothing bar regional pride, it is meaningless from the perspective of the World Cup, and everyone else will have forgotten within a week, assuming they take notice in the first place.
But this is Argentina against Brazil, so the question can never be merely academic.
It is Uruguay's ill fortune that their hopes in the first question collide with Argentina's in the second.
Because the two old rivals meet in Montevideo this Wednesday.
And the only way that Uruguay can guarantee that they will finish fifth is by winning the game - while making sure they do not is the only way that Argentina can be certain of winning the group.
Assuming the form book runs true and Brazil beat Venezuela then Argentina must pick up a point against Uruguay to finish in front of the reigning world champions.
If not, with the sides level on head to head, Brazil's superior goal difference will tip the balance.
Argentina have other reasons for wanting to put up a good show in Montevideo.
First, there is the fact that their footballing rivalry with Uruguay goes back even further than the spat with Brazil.
And secondly because since qualifying four months ago they have seldom looked entirely convincing.
Australia's opponents could be determined by whether more champagne corks were popped in Quito or Asuncion
Their defence rattled and shook its way through the Confederations Cup, until Brazil left it brutally exposed in the final.
And coach Jose Pekerman was far from happy with his side's defending in last month's first-ever World Cup qualifying defeat to Paraguay.
He will be looking for better on Wednesday, when roared on by a packed Centenario Stadium, Uruguay's battery of strikers will present a stiff test - the last real competitive test before next June.
Uruguay have to go for the throat because they know that a draw will probably not be enough.
They are a point ahead of both Colombia and Chile.
If one of them wins, Uruguay have to.
And both are facing opponents who could be excused for over-indulging in the celebrations since Saturday. Colombia are away to Paraguay, Chile are at home to Ecuador, the two sides from the continent who made sure of their World Cup place at the weekend.
Just four days later, can Ecuador and Paraguay possibly be in the right frame of mind to face opponents who will throw everything into one final roll of the dice?
This, then, is the third question of the night. If Uruguay win, then the answer is irrelevant. If not, it could be decisive.
Australia's opponents could be determined by whether more champagne corks were popped in Quito or Asuncion.