Troyes came undone at the death for a second consecutive Ligue 1 game as Dario Cvitanich earned Nice a point from a 1-1 draw at the Stade de l'Aube.
Relegation-threatened Estac had been within 10 minutes of claiming only a second win of the season last time out against Rennes, only for the Breton side to turn it around and win 3-2.
And tonight, Troyes held out for an hour following Stephane Darbion's close-range effort, with Mounir Obbada wasting a gilt-edged chance to make the points safe, but Cvitanich scrambled home a heartbreaking equaliser in the final seconds.
The Argentinian had imposed his will on the game as early as the eighth minute, volleying Camel Meriem's pass against Yohann Thuram-Ulien, who punched clear.
Benjamin Nivet dragged Troyes into the game with a fierce drive at David Ospina before teeing up Jean-Christophe Bahebeck to squeeze the ball just wide of the target.
The hosts' early enthusiasm paid off on the half-hour mark as Darbion cut the ball home from a few yards out thanks to an excellent delivery from Nivet.
Visiting midfielder Eric Bautheac clattered the crossbar three minutes later but Nice found themselves trailing going into the break.
Troyes boss Jean-Marc Furlan might well have urged his troops to keep unhappy memories of last weekend's capitulation fresh in their minds.
But if there had been a motivational speech in the home dressing room at the interval, it was not apparent, as Troyes soon allowed Bautheac to crash another shot against a post.
Obbada had paid attention, though, and tried his luck with a snapshot in front of Ospina, but his accuracy was lacking.
Nice fired a final warning shot across the bows when Didier Digard traipsed into the box unchecked only to fire wide of the target.
Danger seemingly averted, Troyes let their guard down and Cvitanich capitalised on a chaotic goalmouth scramble to shove the ball over the line and extend the hosts' long wait for a victory.