Juan Román Riquelme
After being appointed Boca, Díaz made his official debut in a 4–0 Copa Sudamericana win over last Copa Libertadores champions LDU Quito on 23 September 2008 as an 83rd minute substitution. At La Bombonera team he won the Torneo Apertura (being that his first professional title), which he failed to play it, because he was under the "shadow" of Juan Román Riquelme as the team's playmaker into Ischia's scheme.