Boudebouz netted both of his goals in the first half and Steve Mounie also struck for the hosts at the Stade de la Mosson
Algerian playmaker Ryad Boudebouz scored twice as Montpellier beat Marseille 3-1 on Friday to leave new OM coach Rudi Garcia still looking for a first league win in charge.
Boudebouz netted both of his goals in the first half and Steve Mounie also struck for the hosts at the Stade de la Mosson with Florian Thauvin replying for Marseille.
That was their first goal in Ligue 1 since the takeover of the club by American tycoon Frank McCourt and Garcia's appointment last month, with Marseille having drawn 0-0 with Paris Saint-Germain and Bordeaux in their previous two outings.
Here they fell behind inside four minutes as Boudebouz pounced to turn in the loose ball after goalkeeper Yohann Pele had palmed out a Mounie shot.
Morgan Sanson hit the outside of the post for Montpellier with a superb volley before they doubled their advantage nine minutes prior to the interval.
Souleymane Camara's ball in from the right was deflected by Maxime Lopez into the path of Boudebouz, who took a touch and volleyed in his sixth of the season.
Marseille got one back early in the second half as Thauvin headed in a Romain Alessandrini cross from close range, but Montpellier soon restored their two-goal lead as Sanson picked out Mounie to score.
The result leaves Marseille in mid-table, above Montpellier on goal difference, and confirms to Garcia the size of task that lies in store for him at the southern giants.
Leaders Nice, who are six points clear of Monaco and champions Paris Saint-Germain at the summit, visit struggling Caen on Sunday.
Monaco are at home to Nancy and PSG entertain Rennes.