He refused to sign Laurent Koscielny, says French club's chiefSt Etienne co-chairman Bernard Caiazzo has sent out a warning to Liverpool that Damien Comolli proved to be detrimental to the French club.
Comolli left the Ligue 1 side to be appointed as the Reds' new director of football strategy. Liverpool are hoping he will unearth for them talents like Gareth Bale, whom he took to Tottenham Hotspur.
But his former employers across the Channel have a very negative view of Comolli's accomplishments, or rather the lack of them, during his time with them.
"Damien spent €22 million [£18.7m] of our money on seven players in summer of last year. Only one is a first-team regular now," Caiazzo told The News of the World.
"We gave him the keys to our club and are now in financial difficulties while trying to make free transfers."
"We are not crying into our handkerchiefs.
"You need some humility in football and Damien was convinced he was right 100 per cent of the time. There was never any question of dialogue.
"Damien enjoyed total power in his first year with us. His was the last word on all transfers and that is how he wanted it.
"The manager at the time, Alain Perrin, had not even seen some of the players he was given. Damien was his boss."
However, Caiazzo insists that despite failing to sign the kind of players that Les Verts needed, Comolli spurned the chance to sign Laurent Koscielny for €1.5m [£1.27m]. The defender was recently transferred to Arsenal for a sizeable fee.
Caiazzo said: "His powers were much reduced in January after the failure of his transfer policy the previous summer - and he was not pleased.
"I would have fired him then but my co-chairman defended him for months, even when results were poor.
"I know he sees Damien's departure as something of a personal betrayal. It was a mistake bringing him back to the club.
"We do not have money to throw around and the players he signed for us have lost at least 30 per cent of their value.
"We lost the chance to make a lot of money, too, when Damien refused to sign Laurent Koscielny, for whom [Arsenal boss Arsene] Wenger paid more than €12m [£10.2m].
"Koscielny was in the Second Division with Tours, whose manager used to play for us. He said we should sign him. He'd cost only €1.5m [£1.27m].
"Damien told me that, if you signed Second Division players, you ended up with a Second Division team. So the player went to Lorient and made them a fortune instead.
"My own view of Damien is he favours size and strength as the qualities he goes for first. Perhaps, he will do better with more money at his disposal at Liverpool than he did with us."