The French defender shocked many at the Emirates Stadium during the most recent transfer window when he stated his intention to leave north London after nine years at the club.
The 34-year-old still had another year left to run on his contract with the Gunners, who had originally planned to keep him for the 2019/20 season on the understanding that he would then be allowed to walk away at the end of the campaign.
That certainly seemed the plan when Arsenal signed William Saliba from St Etienne before loaning the teenager back to Les Verts on a season-long loan.
However, Koscielny was of the understanding Arsenal would not stand in his way if he wanted to leave after many years of service and put that theory to the test by requesting he be allowed to move back to France.
When head coach Unai Emery denied his request, the centre-half took strike action, refusing to go on the club's pre-season tour of the United States, while reportedly hitting out over the perceived poor medical treatment he received during his recovery from the Achilles injury he suffered in 2018.
Arsenal responded by stripping Koscielny of the club captaincy but he eventually got his way, joining Bordeaux for £4.5million.
The move left Emery and his transfer team scrambling to sign a replacement in the latter stages of the transfer window, eventually tempting David Luiz across the capital from Chelsea.
Koscielny has stressed in public since the switch that Arsenal had known of his intention to leave for months and DaGrosa has supported his version of events, admitting he was delighted to persuade the ex-France international to move to the Matmut Atlantique over other Ligue 1 sides.
"His desire was to return to France, and particularly to Bordeaux where he has family, in the region. I also think that this concerns this discussion on the subject of young players compared to more experienced players," he told Get French Football News.
"These are things we told him about, and I think that was reasoned in him, and it transcended wage issues. Where does he want to go with his family at the end of his career?"
Koscielny has started three of Bordeaux's four Ligue 1 matches since his switch.