While the Albiceleste kicked off their quest for a third global crown by losing to rank outsiders Saudi Arabia, their Central American counterparts survived a scare to draw with Poland on Tuesday.
Match preview
Since losing to Brazil in the 2019 Copa America, Argentina had embarked on a national record 36-game unbeaten run, and as reigning South American champions, arrived among most pundits' favourites for the final four at least.
Yet, all that momentum counted for little on the first day of their World Cup campaign, as Lionel Scaloni's side let an early advantage slip from their grasp during the space of six second-half minutes at Lusail Stadium.
Leading through Lionel Messi's opener from the penalty spot, the Albiceleste seemed in control of affairs at half time, having seen three other 'goals' ruled out for offside. Two Saudi Arabian strikes shortly after the interval turned the game on its head, however, and Group C's underdogs held out to record a result that will echo through the ages.
With the last of their global triumphs coming back in the summer of 1986, Argentina were already under pressure to deliver a first World Cup trophy for approaching 40 years - particularly in what is set to be Messi's swansong on the game's grandest stage.
Therefore, Scaloni must quickly rally his troops before they tackle the nation that hosted their last success at this level: a Mexico side who sit one point above Argentina in the standings.
Having beaten El Tri in the World Cup's first-ever edition in 1930, the Argentinians have more recently eliminated their Latin rivals twice in the last 16, and they also remain undefeated in the countries' last 10 meetings dating back to 2004.
All of which plays in their favour if precedent is any guide, but the world will now be watching with anticipation as they respond to their seismic shock against the Saudis.
One of several goalless stalemates in the opening week of Qatar 2022, a 0-0 draw with Poland set Mexico's tournament off to a relatively steady start on Tuesday, and in some respects a single-point haul was gratefully received by Tata Martino's men in the end.
After Hector Moreno was deemed to have felled Robert Lewandowski in the box, the Polish marksman failed to convert his golden chance from the penalty spot, as veteran goalkeeper Guillermo Ochoa pulled off a crucial save.
That result sets up a potentially pivotal encounter in terms of qualification from Group C this weekend, as El Tri aim to reach the knockout phase once again.
Now making their eighth consecutive World Cup appearance, the Mexicans have been eliminated at the last 16 stage in each of their last seven attempts, and ex-Argentina coach Martino is the man tasked with bringing a halt to that trend by defying expectation and making the quarter-finals.
La Seleccion last reached that point of the competition as hosts in 1986, when Saturday's opponents went on to lift the trophy thanks to a Diego Maradona masterclass on Mexican soil.
Before this year's squad can dream of emulating such a feat, though, they may well need to at least secure a second point in Lusail, or their hopes of progressing will be left hanging by a thread.
Argentina World Cup form:
L
Argentina form (all competitions):
W
W
W
W
W
L
Mexico World Cup form:
D
Mexico form (all competitions):
L
W
L
W
L
D
Team News
While Argentina's talisman Lionel Messi trained away from the rest of his teammates on Thursday, the 35-year-old playmaker is expected to play from the start this weekend, thus sparing Lionel Scaloni a serious selection headache.
The Albiceleste captain's left leg is his main source of concern, but it seems unlikely that Papu Gomez will be asked to deputise on Saturday. Therefore, Messi should headline an attacking trident also featuring Lautaro Martinez and Angel Di Maria.
Having started on the bench in the loss to Saudi Arabia following a fitness issue, Lisandro Martinez could come in for either Cristian Romero or Nicolas Otamendi as part of Scaloni's back four. Gonzalo Montiel and Alexis Mac Allister are also in contention.
Meanwhile, forwards Angel Correa and Paulo Dybala - the latter only just back from injury - are among several squad members hoping to play their first minutes of the finals.
Another striker recently returned to fitness, Mexico's Raul Jimenez, will aim for promotion to the starting XI. The Wolverhampton Wanderers star made his first appearance for almost three months in El Tri's final friendly and featured from the bench on Tuesday.
Tata Martino may instead turn to Henry Martin again, though, with Hirving Lozano and Alexis Vega offering support from the flanks.
Pachuca's Luis Chavez - who played no part in the CONCACAF qualifiers but worked his way into the team during recent friendlies - should continue on the left side of a midfield trio in Martino's 4-3-3 formation, while Ajax defender Jorge Sanchez starts at right-back.
Argentina possible starting lineup:
E. Martinez; Montiel, Romero, Li. Martinez, Tagliafico; De Paul, Paredes, Mac Allister; Messi, La. Martinez, Di Maria
Mexico possible starting lineup:
Ochoa; Sanchez, Montes, Moreno, Gallardo; Alvarez, Herrera, Chavez; Lozano, Martin, Vega