Ronan O’Gara’s La Rochelle suffered a first home loss in two years as a late try saw Toulouse clinch a 14-11 win to leapfrog the hosts for pole position in the Top 14.
A flying Yoann Huget try five minutes from the end completed a Toulouse comeback from eight points down at half-time to take the victory and inflict a first defeat at the Marcel Deflandre in 21 games on La Rochelle.
In a game played without their Six Nations stars, Toulouse lined up with World Cup-winning winger Cheslie Kolbe at out-half, but defences dominated the game.
Levani Botia’s try was the breakthrough score for the hosts, gathering a kick from out-half Jules Plisson to touch down after 22 minutes.
Plisson added a penalty to make it 8-0 but missed two more either side of half-time and Toulouse began to chip away at that advantage on the resumption with two penalties from centre Zack Holmes.
La Rochelle's Ihaia West kicked a penalty on his introduction after an hour but Holmes responded in kind to set up a grandstand finish.
The losing bonus point leaves La Rochelle two points behind Toulouse with Racing 92 a further point behind.
Elsewhere, Clermont Auvergne won away to the winless Agen, 52-16, to move fourth, six points off Toulouse.