Tevez is not playing, nor is Agüero. Batista has called up a few new players and left some of the old guard at their respective clubs. Argentina is not going to play with their best 11, although Messi on his own is way more than most teams.
This is the complete list of players called up by Batista:
Sergio Romero (AZ Alkmaar)
Mariano Andújar (Catania)
Javier Zanetti (Internazionale Milano)
Pablo Zabaleta (Manchester City)
Gabriel Milito (Barcelona)
Nicolás Pareja (Espanyol, Injured)
Nicolás Burdisso (Roma)
Ezequiel Garay (Real Madrid)
Marcos Rojo (Spartak Moskva)
Nicolás Otamendi (Porto)
Esteban Cambiasso (Internazionale Milano)
Fernando Gago (Real Madrid)
Javier Mascherano (Barcelona)
Ever Banega (Valencia)
Lucas Biglia - At ******* last! (Anderlecht)
Ángel Di María (Real Madrid)
Jose Sosa (Napoli)
Enzo Perez (Estudiantes, replaced by "Pochi" Chavez, Boca Juniors)
Javier Pastore (Palermo)
Lionel Messi (Barcelona)
Ezequiel Lavezzi (Napoli)
Diego Milito (Internazionale Milano, injured)
Nicolás Gaitán (Benfica)
Juan Manuel Martinez (Velez)