The 2005 CategorÃÂa Primera A season was the 58th season of Colombia's top-flight football league. Atlético Nacional won the Campeonato Apertura and Deportivo Cali won the Campeonato Finalizacion.
The Copa Mustang 2005-I is the first tournament of the year. This season included the new team Boyacá Chicó; changing its name from Chico FC, they also moved to Tunja from Bogotá. The season began on February 12, and concluded on June 26.
The second phase of the 2005-I tournament consisted of two groups of 4 teams. This was disputed by the best eight teams from the first phase of the tournament. The winners of each group face in the finals to define a champion.
The Copa Mustang 2005-II was the second tournament of the year. The season began on July 10 and finished December 18.
The second phase of the 2006 tournament consisted of two groups of 4 teams. This was disputed by the best eight teams from the first phase of the tournament. The winners of each group face on in the finals to define a champion.