Top-seeded David Ferrer and No.2 Fabio Fognini of Italy will contest the final of the ATP tournament in the Argentine capital.
Ferrer defeated fellow Spaniard Nicolas Almagro, the 2011 champion, 6-4 6-2 in the semi-finals on Saturday.
Ferrer has won 20 ATP events, including the past two in Buenos Aires.
Fognini defeated another Spaniard Tommy Robredo 3-6 7-5 6-3, coming back from a break late in the second set to oust the 2009 champ.
Fognini won the ATP event last week in Chile, picking up his third singles title.
He has reached the final in a fifth consecutive claycourt event since the French Open.
