Strap yourselves in ... this gets complicated.
Uruguay is at least guaranteed to finish among the two best third-placed finishers that advance to the quarterfinals. Uruguay would stay in that position with a comprehensive loss to Chile and a comfortable win for Japan over Ecuador on Monday and earn a quarterfinal showdown with Brazil.
However, a win over Chile would allow La Celeste to go to the top of Group C and face Peru. If Uruguay draws and Japan doesn't beat Ecuador by seven or more goals, Oscar Tabarez's side would finish second and secure a last-eight date with Colombia.
Peru, meanwhile, concluded its Group A commitments in Saturday's humiliating 5-0 loss to Brazil to finish third in its quartet. That setback forces Peru to watch Monday's battle between Chile and Uruguay with great interest.