On 21 April 1955, the Asociación Central de Football decided that the team will play in the Primera División for the next season, being his first president, Nicolás Abumohor and his first head coach was Francisco Hormazábal. In his first league tournament, the club finished in the ninth place of the table under of Magallanes, playing also the promotion play-offs, in which they failed to be relegated to the Primera B, ending in the second place of the liguilla under of Santiago Morning.