This is a picture of a man who became a great boxer before he ever became famous.  This is one of his training sessions.  He is of course there with other boxers.  They know not all of them will achieve greatness, and their teacher knows this as well.  The training hours are what determines who goes and who stays.  The figure in the background represents the competition of other fighters, but can also be seen as the shadow of the man in the foreground, even though it is not really his shadow.  This represents the man having not only to compete with other boxers, but to compete with himself.  he is the only one that can push himself to train harder, faster, stronger.  This man is able to with the battle against himself, that is why he will become great.  
