Atlético Nacional W

Atlético Bucaramanga's origins can be found in the regional football league of the Santander Department. Like most of Colombia's departments, Santander had a local league. However, they did not have a team capable of competing for national honors. A number of local teams hoped to change that and found a professional club that could aspire to that level.

In 1948, the directors of "Pielroja" (the most recent local champions) invited city businessman Rafael Chaberman to assist in setting up a professional team. Following Haberman's advice, the directors enlisted local businessmen, newspapers, and radio stations to promote a team. A board was assembled with Dr. Elias Solano as president, assisted by managing directors Rafael Chaberman, Vicente Díaz, Miguel González, Juan B. Silva (Treasurer), Manuel José Puyana, Eduardo Villa, Jorge Reyes Puyana, José Vicente Niño, Gustavo Mantilla, Rafael Pérez, Enrique Orduz, and Luis Fernando Sanmiguel.

The club was officially established on 11 May 1949, under the name of Club Atlético Bucaramanga. The key to the club's early foundation was the support of local clubs, and they had it—presidents of Gran Colombia FC (Vicente Díaz Romero), Eleven Friends FC (Luis Alba Pinilla), Girardot FC (Antonio "Terremoto" Durán), Freedom Concordia FC (Jorge Molina Barba) and Pielroja FC (Simón Santander) were all on board and helped supply the team with players. The result was that the club quickly assembled a team composed of players from Bucaramanga, Barrancabermeja and Barranquilla, most of whom had some experience playing at a high level. The three Guerrero brothers (center half Francisco, left wing Juan, and inside right Jorge) were an example of this sort of local talent. The club was also managed by a local, former Millonarios player Francisco "Pacho" Carvajal.

In 1949, the club applied for membership in the Colombian league and was accepted after winning a playoff match with Once Deportivo from Manizales. On 1 May 1949, Atlético Bucaramanga played its first game in the Colombian football tournament, losing to Deportivo Cali 5–1 at the Estadio Alfonso López.

Their first victory came on June 19, when they defeated Boca Juniors de Cali 2–1. The club ultimately finished the season in tenth place out of 12 teams.

Like many other Colombian clubs, Atlético Bucaramanga took advantage of the El Dorado period to sign a host of foreign players. Specifically, in 1950 they signed four Argentine players, a group collectively known as the "Four Musketeers". They were Antonio "Toto" Bernasconi (half-back), Norberto Juan Peluffo (center-half), Aristóbulo Deambrosi (right winger) and José Cayetano Fraccione (goalkeeper), nicknamed "the Flying Fish". This was just the beginning of the club's aggressive pursuit of foreign players, including the signing of Costa Rican forward José Joaquín "El Quincho" Quiroz. Quiroz in particular was known for his spectacular goals. With that group in place, the club managed a sixth-place finish in 1950. The period of success did not last. Bucaramanga had overspent during El Dorado, and the crunch quickly followed. By 1953, the club finished last and in 1954 was out of the league entirely. However, the club did not disappear. They rebuilt, and in 1956 made it back to the league.

Not only that, their connection to Argentina remained intact. The manager responsible for that rebuild, Felipe "Judio" Stemberg, was Argentine, and he brought a number of his countrymen into the side. The most important of those acquisitions was José Américo Montanini, a former striker for River Plate. He arrived at Bucaramanga in 1956, playing for them from 1956 to 1961 and from 1964 to 1968. Montanini's most successful season was the 1958 one, when he led the league in scoring with 36 goals. The club also enjoyed their most successful season yet, finishing third behind champions Santa Fe and runners-up Millonarios.

1960 should have been remembered as an even more glorious season. With Montanini and José Giarrizzo (another Argentinian) leading the attack, the club had a real shot at its first-ever championship. Just three matches remained when the club set out for Bogotá to face the league leaders, Santa Fe. However, the match was a disaster; Santa Fe romped to a 5–1 win, humiliating a Bucaramanga club that looked completely outmatched. Rather than winning the championship, the club finished in a disappointing third place. Much of the blame was put on manager Juan Barbieri, who was literally run out of town during the offseason.

It would be many years before Los Leopardos came that close again. Throughout the 1960s, 1970s, and 1980s, the club was mid-table only in their best years, more frequently finishing towards the bottom. They even had to sit out the 1971 season due to economic problems, selling their place to a team from Cartagena in order to pay off their debts.

The club enjoyed a brief revival in the 1990s with the hiring of Humberto Ortiz as manager. A defensive manager first and foremost, Ortiz's teams were physical rather than stylish, but they were competitive. He spent three years with Bucaramanga, leading them to a third-place finish in 1990, then consecutive mid-table finishes in 1991 and 1992. The club was almost unbeatable at home, losing just six out of 75 matches in their home stadium. However, in 1993 Ortiz was dismissed in favor of Norberto Peluffo, who promised a more open and attacking style of play but delivered a leaky defense in return. In 1994, Bucaramanga finished in last position in the top flight and was relegated for the first time in its history.