There are two different Argentina teams: the one with Lionel Messi and the one without.
A win for either Colombia or Uruguay would represent a huge step in the face to qualify for the 2018 World Cup finals.
Having slipped to seventh in the race to reach Russia, Chile may be forced to go call up a player whose international career appeared to be over.
The Brazilian Championship looks like it might come down to a two-horse race betweem Palmeiras and Flamengo.
In-demand Gabriel Jesus shone for Brazil in the World Cup qualifiers, but a quick return to club action with Palmeiras may not have been in his best interests.
In a highly competitive CONMEBOL qualifying group, Chile's Golden Generation cannot afford to drop too many more points.
A testing World Cup qualifier in the rarefied heights of Quito will provide a tough baptism for new Brazil coach Tite.
Tim Vickery warns that Brazil should not get too carried away by its Olympic success.
Four new international coaches and the return of Lionel Messi coincide with the return of the World Cup qualifiers.
Wednesday has become a crunch moment for the three South American teams in the men’s Olympic football tournament – with hosts Brazil facing elimination