He held the French national middleweight title twice (March 1997 to January 1998) and again from March 1999 to October 2000), the WBC International middleweight title (1997) and the European middleweight title 2002.
After knocking out previously undefeated Cristian Sanavia of Italy to capture the European middleweight belt on May 11, 2002, he became the mandatory challenger for undisputed world champion Bernard Hopkins. On March 29, 2003, the two men faced one another in Philadelphia, Pennsylvania, with Hopkins winning by technical knockout in the eighth round.
As of October 2003, Hakkar's career record is 29 wins and four losses, with 18 knockouts.