Vaca made his debut for the Bolivian national team on October 7, 2001 in a World Cup qualifying match against Ecuador, as a 32nd minute substitute for Sergio Rogelio Castillo.
Sergio Leone | Sergio Franchi | Sergio Ramos | Sérgio Mendes | Sergio Martino | Sergio Osmeña | Sergio Fabbrini | Sergio Aleati | Sergio Sollima | Sérgio Godinho | Sergio Corbucci | Rogelio Mangahas | Sergio Santos | Sergio Pérez | Sergio Marchionne | Sergio Fiorentino | Sergio Badilla Castillo | Bernal Díaz del Castillo | Sergio Vargas | Sergio Tofano | Sergio Oliva | Sergio Mulko | Sergio Mora | Sergio Marchi | Sergio George | Sergio García | Sergio Donati | Sergio Dalma | Sergio Cragnotti | Roberto Castillo Sandoval |