Marseille secured the Ligue 1 title as second-half goals from Mamadou Niang and Lucho Gonzalez helped them to victory over Rennes at the Stade Velodrome.
Auxerre's 2-1 defeat at Lyon had paved the way for OM to secure their first title since 1992 and they got off to a great start when Gabriel Heinze gave them a fourth-minute lead.
The celebrations were put on hold when Jimmy Briand equalised for the visitors, but Niang and Gonzalez ensured that OM added the league to their Coupe de France triumph.
The hosts could not have wished for a better start as Argentina international Heinze stepped up to curl a left-footed free-kick around the wall and beyond the grasp of Rennes goalkeeper Nicolas Douchez and send the Velodrome delirious.
But the visitors refused to role over, Briand shooting wide before Asamoah Gyan came close to finding an equaliser as Steve Mandanda saved his drive from distance.
And when the equaliser came it was well deserved. Gyan freed Jerome Leroy down the left and his cross saw Briand produce a stunning diving header to beat Mandanda.
OM responded well with Mathieu Valbuena picking out Niang, but the striker's effort was blocked by Kader Mangane and the score remained level at the interval.
Niang had another chance shortly after the resumption but the captain pushed his effort wide of the post and Stephane Mbia then headed wide from Valbuena's corner.
But Didier Deschamps' side were back in front in the 76th minute as Laurent Bonnart's cross picked out Valbuena. His shot was parried but Niang was the first to react and tap home.
And the celebrations could finally begin when Gonzalez fired a rasping volley home two minutes later, after Rod Fanni's clearance had come out to the midfielder.
Valbuena than had another chance as Douchez made a sharp save, but it barely mattered as the hosts claimed the title in fine style.
