Gomis netted his sixth of the season to give American owner Frank McCourt some hope ahead of the first match under his tenure.
Marseille prepared for a new US-owned era by squeezing past Metz 1-0 on Sunday thanks to Bafetimbi Gomis's first half goal.
In the last match of the Louis-Dreyfus era, under-performing Marseille gave their long-suffering fans some rare cheer in a miserable season that regardless sees them sit 12th in Ligue 1.
Gomis netted his sixth of the season to give American owner Frank McCourt some hope ahead of the first match under his tenure, due on Sunday next when champions Paris Saint-Germain will provide a daunting test.
Despite their underwhelming start to this campaign, it was at least a third home win this season for Marseille -- as many as in the whole of the last campaign where they finished 13th.
The game itself was forgettable in a Velodrome that was well under half full.
The winning goal came on 13 minutes as Gomis was quickest to the rebound after Metz goalkeeper Thomas Didillon had pushed out his header from a corner.
Marseille had chances to close out the match through Clinton Njie and Gomis in the second half but were left sweating as Japanese defender Hiroki Sakai almost scored an own goal two minutes from time.
Metz pushed late in the game but perhaps lacked confidence following their 7-0 mauling at the hands of Monaco last time out.
In the day's other games, Saint Etienne had a somewhat generously-awarded penalty deep into stoppage time to thank for rescuing a point at home to lowly Dijon.
Nolan Roux converted from the spot to cancel out Pierre Less-Melou's 22nd minute opener.
It also finished 1-1 between Rennes and Bordeaux.
Nice went four points clear at the top with a 2-0 win over Lyon on Friday night as Monaco lost 3-1 at fourth-placed Toulouse.
PSG moved above Monaco on goal difference with a 2-1 win at Nancy on Saturday thanks to early goals from Lucas Moura and Edinson Cavani.