For the uninitiated, the top four countries from South America qualify directly for Russian Federation with the fifth-placed team entering the intercontinental playoffs to play New Zealand.
As for Peru, Thursday's draw left it a win away from automatic qualification. With qualification secure, Brazil have taken the foot off the pedal, drawing with both Colombia and Bolivia.
- A from that "draw" could see Argetina move above Chile and Colombia - as long as both the teams lose by a two-goal margin.
"The team that hauled itself to the World Cup final three years ago was heavily reliant on the inspiration of Messi and the grit of Javier Mascherano".
Uruguay, Chile, Colombia, Peru, Argentina and Paraguay all harbour hopes of qualifying automatically with just four points separating all six nations with just one fixture remaining. For the tour before the end of the selection, Ecuadorians with 20 points and goal difference 25-26 take 8th place in the group from which they will not move anywhere. They need a single point against the ninth-placed team.
Argentina, on paper, look favourite for three points, but the way things have gone for the Albiceleste this campaign, anything is possible. It's number-crunching time for Argentina and six other South American countries still vying for places in next year's World Cup in Russian Federation.
The 2014 World Cup finalists face their moment of truth after a series of uninspiring performances that has the sporting world scratching its head at how a squad bristling with so much attacking talent has found scoring so hard.
It is now 456 minutes since any Albiceleste player found the net from open play, and despite being heavy favourites against Peru in their last game, they were inept in attack, even with five-time Ballon d'Or victor Messi pulling the strings.
Portugal's Cristiano Ronaldo vies for the ball with Hungary's Adam Lang during a FIFA World Cup qualifier. A win for La Blanquirroja will guarantee them a play-off place, and should that result be accompanied by draws or defeats for Chile or Argentina, then they will go straight through.
If the pressure on the team, the position they find themselves in and the state of the pitch wasn't bad enough their record in Ecuador makes things even more hard.
But Argentina has struggled to score in qualifying.
Martino also quit but Messi came back under new coach Edgardo Bauza, although the team did not improve and he was replaced by Sampaoli. Tonight, Messi and his compatriots travel to Ecuador, with only a win likely to be enough.