In the 1996 season, the club signed great players, having a great team with Clarence Acuña as central midfielder, in the creation the Argentine playmaker Gerardo Martino, a footballer from Argentine Primera División side Newell's Old Boys, whilst were released as strikers: Carlos Poblete and Ariel Cozzoni. However, the team lost the category, relegating to the Primera B, after a finish under Regional Atacama in the table's bottom. Two years later, under the orders of René Serrano, the team achieved promotion to the First Division (Primera División). In 1999, the club of Rancagua finished in tenth place, in which Mario Núñez and Jaime González also became the most successful goalscorer pair in the Chilean football with 57 goals between both strikers. In the 2001 season, with financial problems and a poor season, the team lost the category, returning to the Primera B with the coach Guillermo Páez in the charge.