The Argentinean Football Association has confirmed Carlos Tevez has suffered a twisted right knee which will keep him out of Wednesday's crunch clash with Paraguay.
Tevez pulled up in his country's critical 3-1 defeat to Brazil in Buenos Aires, which has put the South American giants in real danger of not qualifying for South Africa 2010.
Argentina need to win in Asuncion in midweek to avoid their qualification hopes slipping out of their own hands.
Tevez's injury is likely to give Manchester City a first test of the strength in depth of a squad expensively assembled over the summer.
Tevez was not the only casualty of the Argentina-Brazil clash as domestic team-mate Robinho also picked an injury in the game.