[2] In the 2006 Apertura, Lux lost his job to emergent talent Juan Pablo Carrizo[3] and, a few months after, was cut from the squad by coach Daniel Passarella.

[5] Lux signed a four-year deal with RCD Mallorca for 2007–08,[6] as a backup to youth graduate Miguel Ángel Moyá, but benefitted from an injury to the latter to appear in ten La Liga matches during the season.

[7][8] In his second year, the same occurred: Moyá was again downed with physical problems and Lux was promoted to starter,[9] but lost his job in January 2009 with the signing of Dudu Aouate from Deportivo de La Coruña.

[18] As a starter during the 2004 Summer Olympics (all six matches, no goals conceded), Lux was instrumental in the gold medal triumph of the Argentina national team, who scored 17.

[19] He made his full debut on 9 March 2005 in a 1–1 friendly draw against Mexico, as manager José Pékerman only fielded players based in the Argentine league.