Abdennour was born in Sousse, Tunisia. His preferred position is a left winger, although he regularly plays at defender. He started his career at Etoile Sportive du Sahel in 2008. During his spell with Etoile, he was a fan favourite despite being one of the youngest players in the team. In the 2008–09 season he scored five goals for his club, but they missed on the title and finished third.
On 14 January 2010, Abdennour signed a half year loan deal with SV Werder Bremen which initially saw him stay at the club until the end of the 2009–10 season. Bremen had the contract option to sign him permanently. Abdennour made six appearances for Werder Bremen. Following the 2009–10 season, Werder Bremen did not take up the option to sign Abdennour and he returned to Étoile.