 Sosa stayed with Estudiantes for the remainder of the Clausura 2007 tournament.On 29 October 2009, Bayern Munich announced that the Argentine midfielder will be loaned to his former club Estudiantes for the remainder of the season, even though he was not registered to play the 2009 World Club Championship finals.On 30 August 2010, Sosa joined Italian side Napoli for €2 million fee (including €100,000 solidarity contribution to youth clubs of Sosa), signing a four-year deal.