After confirming the 23-man squad on Monday, the news that first-choice goalkeeper Sergio Romero will miss the entire tournament through injury comes as a bitter blow for head coach Jorge Sampaoli.
The Manchester United goalkeeper was expected to play a key role for the South American giants and achieve the 100 cap milestone in Russia, as he currently stands on 94 appearances.
Willy Caballero and Franco Armani were the other two goalkeepers called up by La Albiceleste and a replacement is expected to be named over the coming days.
"Sergio Romero suffered today a joint blockage in his right knee that will leave him out of the squad," The Argentine Football Association confirmed via their official Twitter account on Tuesday evening.
Argentina were drawn in Group D for the upcoming global showpiece along with Iceland, Croatia and Nigeria.