Laurent Koscielny’s comeback ought to have been the feel-good Arsenal story of the year. Faced with a career-threatening injury, he fought back to reclaim the captain’s armband and lead his team out in a European final.



Sadly, the tale didn’t end as Arsenal might have hoped. Defeat in Baku was just the prelude: when Koscielny refused to travel on the club’s pre-season tour of America, it effectively made his place in the squad untenable. Within a month, he had departed for Ligue 1 and Bordeaux.



As Arsenal’s executive team circle their wagons rounds the embattled Unai Emery, they are keen to stress that the head coach has been working under difficult circumstances. Presumably, Koscielny’s departure figures prominently in their thoughts. It is quite remarkable that Granit Xhaka is not the first Arsenal captain to go rogue this year.



However, it seems the coach is not without blame in this situation. While a return to...