Both sides have taken 10 points from a possible 12 thus far, with Saint-Etienne playing out a 2-2 draw with Nantes and Rennes overcoming Monaco last time out.
Despite the fact that Saint-Etienne's winning streak was ended at the hands of Nantes last weekend, the league leaders have enjoyed a particularly strong start to the campaign regardless.
Had it not been for two late strikes from Moses Simon and Renaud Emond, Saint-Etienne would have registered four wins from their opening four games without conceding a single goal, but Claude Puel's men are still one of only three sides yet to taste defeat in the 2020-21 Ligue 1 campaign.
While Saint-Etienne are currently atop the rankings heading into gameweek five, Lille - currently two points worse off - have the chance to temporarily leapfrog Puel's men should they take all three points against Nantes on Friday evening.
The hosts have already enjoyed back-to-back 2-0 home victories against Lorient and Strasbourg in the early stages of the new campaign, but a clash with fellow high-flyers Rennes represents a different kettle of fish for the table-toppers.
Rennes are gearing up for their second top-of-the-table crunch match in as many weeks following their encounter with Monaco last Saturday - a dramatic game in which Julien Stephan's men ultimately prevailed.
Both sides went into the tie following two wins and a draw from their opening three matches, and Rennes looked to be heading for their first defeat of the campaign after Wissam Ben Yedder opened the scoring for Monaco.
However, Julien Stephan's men displayed their Champions League credentials as they turned the game around in the second half, with goals in the last 10 minutes from Steven NZonzi and Adrien Truffert propelling Rennes to their third Ligue 1 victory on the bounce.
Les Rouge et Noir will no doubt go into this game feeling capable of taking another three points off an early high-flying team, and a win here would put Rennes in a brilliant position before their Champions League ventures begin next month.
The two sides met once in the league last season - Rennes winning that fixture 2-1 - although Saint-Etienne triumphed over Stephan's men by the same scoreline in the semi-finals of the Coupe de France back in March.
Saint-Etienne Ligue 1 form: WWWD
Rennes Ligue 1 form: DWWW
Saint-Etienne's Wesley Fofana was left out of Puel's squad to face Nantes amid links with Leicester City and West Ham United, but the youngster's absence was believed to be a precautionary measure following fatigue so Fofana could come back for the showdown with Rennes.
Sacha Boey is back from suspension but Hamari Traore is unlikely to be displaced at right-back, while last weekend's match-winner Truffert - initially brought on against Monaco to replace the injured Faitout Maouassa - will be handed a start here.
Reports have suggested that Maouassa could be sidelined for around two months with the ankle injury he sustained in the clash with Monaco.
Saint-Etienne possible starting lineup:
Moulin; Sissoko, Moukoudi, Kolodziejczak, Macon; Camara, Youssouf; Bouanga, Aouchiche, Nordin; Hamouma
Rennes possible starting lineup:
Salin; Traore, Da Silva, Aguerd, Truffert; Camavinga, Nzonzi, Bourigeaud; Raphinha, Guirassy, Terrier
We say: Saint-Etienne 1-2 Rennes
Saturday's showdown promises to be a fascinating encounter between two sides enjoying excellent starts to the new campaign. However, Saint-Etienne have a few injury concerns to deal with and the Rennes faithful will be anticipating another strong performance following their side's thrilling victory over fellow high-flyers Monaco, so we are backing the visitors to scrape a narrow win in this top-of-the-table clash.