Saint-Etienne seemed to be awoken by the goal and made a spirited effort to try and level proceedings that came in the 19th minute.
The Saints were awarded a penalty when Mehdi Zerkane brought down Khazri in the area and the Tunisia international stepped out to dispatch home his spot-kick.
Khazri then gave his side the lead four minutes later when he connected with Adil Aouchiche s cross before firing into the back of the net.
The attacker completed his hat-trick in the 72nd minute, converting from the penalty spot after Jimmy Briand was adjudged to have handled the ball in the area.
Ligue 1 : Les Verts dominent les Girondins et foncent vers le maintien (analyse et notes)
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ASSE : Le groupe des Verts pour la réception des Girondins de Bordeaux
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Foot PSG - ASSE : Une banderole fait scandale, ça va trop loin ?
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