Ligue 1's two most successful clubs meet in a crucial clash on Sunday, while unbeaten Paris Saint-Germain visit Toulouse on matchday eight.
Saint-Etienne last conquered France in 1981, but Marseille have claimed five crowns since to join them on 10 league titles and such success means the clubs share a fierce rivalry.
With Marseille in pole position and Saint-Etienne two points back in third, that rivalry will intensify at the Stade Velodrome.
After a stuttering start to the campaign, Marseille have won five straight matches, scoring 16 and conceding just one in the process.
Coach Marcelo Bielsa has, however, tempered talk of the title.
Marseille's form has been thanks to Dimitri Payet and the finishing of Andre-Pierre Gignac, who is Ligue 1's eight-goal leading marksman.
"I'm not Zlatan and I'm not [former Marseille striker] Jean-Pierre Papin," said Gignac. "I'm not on their level. But I give my all because of the love I have for the club.
"I have recorded by best goals tally at this stage of a season. I'll try to improve it against Saint-Etienne."
Saint-Etienne have, worryingly, only scored four goals in their previous eight matches, while the last six instalments of the fixture have produced just eight goals.
PSG, up to fourth after winning for the first time in four outings in all competitions, visit Toulouse having tasted victory in the teams' last 10 meetings.
Bordeaux, Lille and Metz, in second, fifth and sixth, will expect to win at home to Rennes, Bastia and Reims respectively.
Nantes host Lyon in a battle between sides just inside the top half.
Lyon are fresh from a 4-0 win over Lorient in which 21-year-olds Nabil Fekir and Clinton N'Jie thrived.
Monaco relieved pressure on themselves following a disappointing start to 2014-15 with three successive 1-0 victories.
Now 11th, Leonardo Jardim's men entertain a Nice team one place beneath them.
Evian, who finally got their first win of the campaign on Wednesday, travel to fellow strugglers Lorient, while Lens host Caen in another battle at the bottom.