Coup de la Ligue wrap: Saint-Etienne, Lille progress
Romain Hamouma got Saint-Etienne on their way with a goal in the 10th minute, receiving a pass from the left wing before turning and striking a powerful shot into the bottom corner.
In the 68th minute, Hamouma doubled the visitors' lead, bursting in from the right-hand side onto a through ball from Saint-Etienne's defensive half and placing his shot between the near post and Sochaux goalkeeper Pierrick Cros.
Saint-Etienne wrapped up the scoring in the 89th minute when Alejandro Alonso picked up the loose ball in the box, having mistimed his own header, and scored, thanks to a deflection off a Sochaux defender.
In other Coupe de la Ligue results, Lille defeated Toulouse 1-0 thanks to a goal in extra time, while Troyes won 2-1 away to Monaco and Rennes overcame Arles 1-0.