However, he finished the second half of the season (2009 Clausura) as a starter as the team's right winger, also playing in the final game against Huracán, when Vélez obtained the national championship.
In the ninth fixture, Racing faced Belgrano and Díaz made his fifth assist in the tournament after sending a precise head to scorer Gustavo Bou.
On the last fixture game against Godoy Cruz, Díaz assisted teammate Ricardo Centurión to score the goal that would give Racing the national title after 13 years.
In January 2010, he was called by Argentina's coach Diego Maradona for an Argentine league-based squad to play a friendly match against Costa Rica.
In November of that year, he was called by Sergio Batista, Maradona's replacement as Argentina's head coach, for another squad of local league players to train twice weekly with the national representative.