Aubameyang is now on the brink of signing for the Gunners after clashing with BVB management.
However, Italian transfer expert Gianluca di Marzio says the tension has been growing for 18 months after he was blocked from leaving BVB last summer. It's suggested Aubameyang was assured he would be allowed to leave over the summer after being prevented from returning to AC Milan in 2016.
BVB talked Aubameyang out of the move after losing Ilkay Gundogan, Henrikh Mkhitaryan and Mats Hummels, with assurances he would be allowed to leave in 2017. However, BVB played hardball this past summer - much to the frustration of Aubameyang.
The striker is now expected to join Arsenal for a fee of €60-70m.