Bledion Guga clumsily pushed Sutton inside the box and the striker, who had missed from the spot in Vlore, handed the ball to Forbes, who sent Mocka the wrong way after 28 minutes.
Dzeko was hauled down clumsily by Gardner and Kolarov prowled on the edge of the box before curling the ball deliciously to the right of a bemused and wrong-footed Foster.