A last-minute finger-tip save deprived Florian Thauvin a double and Marseille the three points as Saint-Etienne fought for a 2-2 Ligue 1 draw on Friday with a goalkeeping gaff from the visitors the key moment in the match.
The result means Paris Saint Germain are ten points clear ahead of their trip to Toulouse Saturday and free to concentrate on a Champions League clash with Real Madrid in midweek.
The snow was relentless in central France but over 30,000 home fans never stopped singing as their resurgent side made it seven points from nine.
Thauvin buried a cracking left-footed volley from a deep cross right in the bottom corner of Stephane Ruffier's goal on four minutes after his marker had slipped in the snow.
But Kevin Monnet-Paquet then held his nerve to slot a careful shot past OM stopper Steve Mandanda and a back-tracking Luiz Gustavo on nine minutes to make it 1-1.
Ruffier was again key as he raced out of his goal with Valere Germain bearing down on him and belted the ball to safety when a goal looked more likely.
But Marseille again took the lead on 20 minutes when Morgan Sanson's powerfully shot found the back of the net.
The game turned as Marseille 'keeper Steve Mandanda injured himself with a goal-kick, limping off clutching his thigh.
An absolute howler from reserve 'keeper Yohann Pele allowing the hosts back in as he missed a deep cross before substiture Robert Beric chested the ball home on the line on 74 minutes.