For 90 minutes the Iranians had held firm against one of the tournament favorites and nullified one of the world’s finest players with a superbly disciplined performance.
But the truly great deliver when their teams need it the most and with one of the surprise results of this World Cup just moments away, Messi took advantage of just enough space to curl a beautiful left-foot shot into the top corner and put his team into the last 16.
It was hard not to feel sympathy for the Iranian players who slumped to the floor at the final whistle, despairing that their concentration and exertion had come to nothing.
There was just over two minutes of stoppage time remaining before they would have become national heroes and earned the justified respect of the football world.
At the same time though, Messi had provided a reminder of one of football’s basic truths – that while coaches can devise tactics and systems, the inspiration of the truly gifted individual is so often what wins matches.
Queiroz had set out to replicate the success he enjoyed as Manchester United assistant in 2008 when he helped Alex Ferguson mastermind a 1-0 aggregate win over Messi’s Barcelona in the Champions League semifinal.
As well as serving as Portugal and Real Madrid coach, the much-travelled and often under-estimated Queiroz, has worked in United Arab Emirates, the United States and Japan and clearly has acquired an ability to transmit his astute tactics to average players.
Four-times world player of the year Messi was double-marked throughout and Iran’s midfield acted as a second line of defense with captain Javad Nekounam marshalling the operation and leading by example with his firm challenges and astute positioning.
Argentina had their chances in the first half, but twice Iran keeper Alireza Haghighi came to the rescue, to foil Gonzalo Higuain and Sergio Aguero, and on another occasion Angel Di Maria fired over the bar.
But as the game progressed the trident attack of Messi, Higuain and Aguero, arguably the most talented front-line in the tournament, found themselves crowded out, while Di Maria was unable to find the space to exploit on the flanks.
After the break, everywhere Argentina turned they came up against an Iranian harrying them, closing them down and blocking off their route to goal.
The goalless draw is often raised by critics of the game as a supposed weakness in the sport but Iran’s defending – with honesty and without cynicism or excessive foul play, made for a fascinating encounter.
A team which lost at home to Guinea in March and could only draw with Angola in May, was proving unbreakable in the face of a side many expect to see in the final on July 13.
And it could have been even worse for the Argentines – the often isolated striker Reza Ghoochannejhad twice forced Sergio Romero into saves as Iran threatened on the counter-attack.
Argentina coach Alejandro Sabella was left with no alternative to simply switching his strikers – taking off Higuain and Aguero for Rodrigo Palacio and Ezequiel Lavezzi in the hope that their freshness might just make the difference.
But it was Messi, who just as against Bosnia in the opening game had been subdued for most of the game before scoring, who made the difference.
And as so often, he did so with a technical brilliance that, no matter how many times it is produced, continues to astound.