I think this is a well planned shot, except for one quirk I believe would help improve this further. I really like the shallow DOF, however its focus is on the ace card in the middle where as the colour focus is the King. If you had kept the isolated colour and the DOF focus together on the King the impact would be much greater.
Still I really like the slight grunge of the cards, the tones of black and grey, along with your choice of isolated colour. The composition along the lines of the rule of thirds is well done and all lines (as well as colour) draw your eyes towards the King.
Still if the shallow depth of field were only on the King this would have been a 100% well executed shot. Very nice.
i agree with the critique , maybe a focus on the base of the king's card would have left enough DOF to include the hole King card from bottom to the top and even the top of the ace card. non the less it is a wonderful shot