I think there's definite potential with this shot. One thing to look out for are things sticking out of your subject, like the rock coming out of his shoulder. That was the first thing I noticed. More depth of field would also help bring the subject out of the background.
Hmm horizontal is leaning to the right and that piece of brick is sticking out of his shoulder.. it looks also a bit gray-ish. I think you could've got more out of this picture with a better composition and post processing.
Nearly fabulous, but it feels too loose on the figure, and too tight on the rock. Just a little sharper, and perhaps a little closer to the subject, and I'd have marked higher.