His first major success came in 2003 when he won the Canadian canoe (C-1) 500m gold medal at the Pan American Games in Santo Domingo, Dominican Republic. Two weeks later, at the world championships in Gainesville, USA he reached two finals, finishing fourth in the C-1 500m and eight in the C-1 1000m.
Chacon competed at the 2004 Summer Olympics, this time in the C-1 1000m. He placed third in his initial heat with a time of 3:54.250, qualifying for the semifinals. There, he placed second, this time at 3:52.260 to qualify for the final. In the final, Chacon placed eighth with a time of 3:54.957.
After the 2004 Olympics he and Serguey Torres were chosen as Cuba's new C-2 pairing for international competitions. Replacing the former world champions and Olympic medallists Ibrahim Rojas and Ledys Frank Balceiro was no easy task but the Aguilar and Torres enjoyed immediate success at the 2005 World Championships in Zagreb, Croatia. They won medals in all three C-2 races - silver in the 1000m and bronze in the 200m and 500m.
