#9 Alex Song
If there is one position on the field which Arsenal have still not been able to replenish with the same quality, it is the defensive midfield. Having to fill in the large boots of Patrick Viera, Alex Song had slowly but steadily established himself as the rock of a young Arsenal midfield developing all attributes that allowed others to express themselves while he would hold the fort.
His role in the team became even more critical when he added to attacking side of his game when he could find the space between the lines and be the extra man to play the final ball.
Post his departure to Barcelona, Arsenal have had a whole lot of options to try in the form of Abou Diaby, Francis Coquelin and more recently Granit Xhaka, but no one has been consistent enough to lay claim on it like the Cameroon international once did.