It's a good concept, the shirt just isn't very well done. Why not do like the scene where he's running up the stairs then people would get it imediately and not have to look for a second.
his neck - is way too skinny, boxers have nocks like tree trunks and his head is so huge that neck would snap under the weight. When I was 17 or so I wanted to be a boxer so bad and I went to a women's boxing club and 1.) they had pictures of Tanya Harding (who is a professional boxeer) hanging like she was a goddess 2.) i could not weigh in enough for the featherweight and I have asthma - so dreams were crushed. and that is the end of my short and pointless story.
About my design