His first major senior medal was a bronze at the 2002 Ibero-American Championships in Athletics – an honour he repeated in 2006. Nava competed at five editions of the South American Championships in Athletics from 2001 to 2007, having a best pole vault finish of fourth in 2001 and 2006. He was a participant at the Pan American Games in 2003 and 2007, and also the 2003 Summer Universiade.
He began his international career in 1998 and took silver medals behind compatriot Jorge Naranjo at the South American Youth and South American Junior Championships. He succeed Nava as the region’s top young vaulter with championship records of 5.00 m (16 ft 4+3⁄4 in) and 5.10 m (16 ft 8+3⁄4 in) to win the youth and junior titles in 2000. He defended the junior title in 2001 before falling behind Brazil’s Fábio Gomes da Silva in 2002. He also won a silver behind Naranjo during this period at the 2001 Pan American Junior Athletics Championships. He represented Chile at the 1999 World Youth Championships in Athletics and the World Junior Championships in Athletics in 2000 and 2002.
He also won gold medals at the 2007 ALBA Games and the South American University Games in 2004.