Argentina recall Gago for qualifiers
Sabella, whose team beat Chile 4-1 at home before being upset 1-0 away to Venezuela in qualifiers earlier this month, named AS Roma midfielder Gago and Guinazu in a 21-man squad on Thursday.
He also recalled Napoli forward Ezequiel Lavezzi and left-back Luciano Monzon of Nice. Newcastle United winger Jonas Gutierrez was one of the players dropped.
Argentina are at home to Bolivia on November 11 and visit Colombia four days later.
Nine South American teams play in a single qualifying group while Brazil qualify automatically as hosts of the 2014 event.
Goalkeepers: Sergio Romero (Sampdoria), Mariano Andujar (Catania).
Defenders: Martin Demichelis (Malaga), Nicolas Burdisso (AS Roma), Federico Fernandez (Napoli), Luciano Monzon (Nice), Pablo Zabaleta (Manchester City), Marcos Rojo (Spartak Moscow).
Midfielders: Javier Mascherano (Barcelona), Ever Banega (Valencia), Fernando Gago (AS Roma), Javier Pastore (Paris Saint-Germain), Nicolas Gaitan (Benfica), Jose Sosa (Metalist Kharkiv), Pablo Guinazu (Internacional).
Forwards: Lionel Messi (Barcelona), Angel di Maria, Gonzalo Higuain (both Real Madrid), Ezequiel Lavezzi (Napoli), German Denis (Atalanta), Sergio Aguero (Manchester City).