He attended Madine academy in Meuse briefly before he made his league debut in November 2002.

In November 2006, Chrétien had a penalty saved by FC Basel striker Mladen Petrić after Basel goalkeeper Franco Costanzo was sent off in an UEFA Cup group stage match.

On 1 September 2011, Chrétien joined Turkish side Bursaspor on a three-year contract.

A French U21 international, Chrétien earned his first call-up from his father's native Morocco in a friendly against Tunisia on 7 February 2007.

[1] He was a member of the Morocco squad that participated in the 2008 African Cup of Nations.