Three teams share the lead in Ligue 1 heading into Christmas after Marseille joined Lyon and Paris St Germain at the summit by beating St Etienne.
In what is turning into one of the most exciting title races in years, Elie Baup`s men were once again indebted to one of the Ayew brothers - Andre on this occasion - as they kept themselves in the thick of things.
Ayew scored the only goal of the game on the stroke of half-time to see off Les Verts, who themselves have gone from genuine title contenders to mid-table fodder over the past month.
They are now 11 points behind the leading trio, who are headed by PSG on goal difference, and were guilty tonight of failing to test home goalkeeper Steve Mandanda enough.
Christophe Galtier`s men actually started brightly, keeping the ball and defending with a high line, but they were unable to do little more than hog possession and when Marseille got going, they showed them how it was done.
Mathieu Valbuena laid on the game`s first chance with 36 minutes gone, whipping in a fizzing cross that Stephane Ruffier did well to deal with, before the same player`s cross landed on the head of Joey Barton who should have done better with a free header.
Marseille had been increasing the tempo and with 45 minutes on the clock they went ahead, with Ayew`s brilliant header making good of Rod Fanni`s cross.
St Etienne knew they needed to make more of a game of it in the attacking third after the break and they at least tried, Josua Guilavogui leading the way with a 20-yarder that went over, before Mandanda got down well to make a stunning save from Pierre-Emerick Aubameyang, although the offside flag had already been raised.
Aubameyang was onside when he ran on to Francois Clerc`s pass and rounded Mandanda, but Fanni got back to deny him on the line, and that was as good as it got for the visitors, with Marseille seeing it out and nearly adding a second as Andre Ayew, fed by brother Jordan, was denied by Ruffier.