Pastore scored his first senior international goal on 31 March 2015, in a 2–1 friendly win over Ecuador, at the MetLife Stadium, in New Jersey. Later that year, Pastore was selected by coach Gerardo Martino for the 2015 Copa América, and started in the team's opening fixture against Paraguay in La Serena. At the semi-final stage, Pastore scored the team's second goal and assisted Ángel Di María for the third as Argentina defeated Paraguay 6–1 to reach the tournament final. In the final against hosts Chile on 4 July, Pastore came off for Éver Banega in the 81st minute; following a 0–0 draw after extra-time, Chile claimed the title with a 4–1 penalty shoot-out victory.