Anthony Martial converted a stoppage time penalty as Champions League-chasing AS Monaco secured a 2-1 half-time lead over Toulouse at Stade Louis II.
The hosts came into the encounter knowing that victory would see them move five points clear of Marseille in fourth.
Only two minutes had elapsed before Leonardo Jardim's side made inroads toward returning to the competition that helped them enhance their reputation this season.
Monaco, who eliminated Arsenal in the last-16 stage, almost went ahead through Geoffrey Kondogbia, whose effort looked to be sailing into the top corner before Ali Ahamada managed to make a crucial save.
Ahamada was powerless on the 10-minute mark, though, as Bernardo Silva latched onto Yannick Ferreira Carrasco's ball and his deflected effort left the Toulouse stopper with no chance.
The visitors toiled in the final third before restoring parity on 26 minutes, as Oscar Trejo played in Martin Braithwaite and the Dane made no mistake.
Braithwaite was proving a menace as Toulouse finished the half on top, and lightning almost struck twice but the Denmark international's 25-yard strike glided painfully wide.
Just when it seemed as though the sides would be level at half time, Martial slotted a penalty in the dying embers of the half, after Trejo conceded the spot kick.
