The 22-year-old Argentine helped Quilmes gain promotion to the first division last year. He played 21 games and was a teammate of Paolo Cardozo, selected by the Galaxy in the first round of this year's MLS draft.
In addition, the Galaxy said Friday that goalkeeper Donovan Ricketts received a U.S. green card and will no longer fill an international roster slot. Ricketts has spent two seasons with the Galaxy and played for Jamaica at the 1998 World Cup. He has made 76 international appearances.