The attacking midfielder was the Ligue 1 side’s first signing of the January window, arriving on a six-month loan from Bologna.
St Etienne were desperate to add creativity to their side and Mounier seemed a decent fit. Within hours, the backlash had begun though.
Supporters’ group The Green Angels put up a banner at the club’s Geoffroy Guichard stadium, reading, ’Mounier, our colours will never be yours.’
The player, who grew up in a St Etienne-supporting family, then started to receive death threats, and was withdrawn after being named in the matchday squad for the side's next match.
His crime? Having spent seven years at arch-rivals Lyon - and later swearing at a section of St Etienne fans after scoring two goals against them for Nice.
Such things are not forgotten quickly by football fans.
Sporting director Dominique Rocheteau, the legendary French midfielder, was either not aware of the incident, or had badly misjudged the level of bad feeling that remained towards the player.
Now, as they say, St Etienne were between a rock and a hard place.
Bologna didn’t want the player back (and weren’t legally obliged to take him), but his presence threatened to place a poisonous cloud over the rest of their season.
Fortunately, Atalanta agreed to take him at the end of January, but not before some damage had already been inflicted.
It was too late to find an adequate replacement, time and money had been wasted, and the club’s reputation – and relationship with the fans – had been somewhat damaged, even though coach Christophe Galtier insisted: “Sometimes one does not need to be ashamed to take a backward step.”
Julien Simoes, recruitment partner at IBM, says: “All of this could have been avoided. I don’t think there is space for assumption and ‘gut feeling’ in this era of all things cognitive and data when it comes to a top football club and hiring players.
“If Saint-Etienne had had a solution [like Watson], not only would Mounier not have been a choice but a better player could have been targeted not only for his skills but also for personality resulting in an overall better cultural fit for the club.”
Watson could have trawled ‘unstructured data’ such as interviews, reports and social media activity and, perhaps more importantly, gauged the reaction of St Etienne fans to the potential signing.
They could have put it out there that they were considering signing the player and then assessed the response across social media.
As it was, former player Francois Clerc was left to sum it up.
“I can understand that fans don’t want to see a player who insulted them in the past,” he said.
“I don’t understand why the club took him in the first place.”
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