Under the abbreviated name ESM Challans in 1971 the team was promoted to the first division of the French Basketball Championship, the National 1.
In addition, the same year the club won the French basketball trophy for unterklassige teams against CRO Lyon.
On his third participation in the Korać Cup the club for the first time succeeded in gaining the last 16, and thereby reach the group stage, but where managed just one win in six games.
In the Korać Cup participation 1986-87 the team sold properly at Estudiantes Madrid and Mobilgirgi Caserta, but failed in the group.
In 1987 although Challans still qualified for the inaugural play-offs for the French League and was there until the quarter-finals, the club withdrew voluntarily from the professional basketball back and started again in 1993 in the fourth division.