Let me add to that, that the scale is all wrong. The bench is WAY too big for the size of the player. There's a sense of WA room and tele player, the focal lengths don't match. It's REAL important to have both focal lengths and camera height match between the two shots, in addition to the lighting consistency Cory mentions.
On first glance it's pleasing, no question, but you have to work on the details of set-up and compositing to take it to the next level.
Get the book "Photoshop Compositing Secrets" by Matt Kloskowski or watch some of his and Joel Grimes videos over at Kelby Training. They are some of the best.
here is one I did not too long ago. it's not perfect but maybe it will help.
The background is one I bought but I edited it to match the feel I wanted. I shoot the portraits at 21-24mm on a full frame and that usually fits the backgrounds pretty well. I light them with the joel grimes lighting, 2 gridded strip banks or softboxes behind and a beauty dish high in the middle front.
