Looming Over Lefty
Just as game 8 of the World Series is about to start with Lefty taking the mound for the Sox, we see a man looming over Lefty's wife's right shoulder in the stands. The image is a hard reminder to him of what is at stake if he doesn't lose the game; his wife will be killed.
Dinner for One
Arnold Rothstein is an incredibly wealthy and powerful man as he is the one that the fixer goes to in order to get the funds to set it all in motion. When Sullivan arrives in Rothstein's home we see the man having dinner completely alone, with no sound. The shot tells us without directly implying it with a wide shot, that Rothstein is a lonely, isolated man and he's most likely done it to himself.
Pissing it All Away
In the bathroom early in the film we find Chick and Swede using the urinals as they talk about setting up the fix for the Series. This image is showing us that these two are pissing away the opportunity to earn victory and become champions, and when Chick gets jumpy when Burns and BIlly walk in he pees on himself. This is showing us that he's not going to get away with it so cleanly.
Duality
Before exiting the restroom after conspiring to fix the World Series we see Swede and Chick standing before the mirror. The image shows us the now dual nature of the two men. And, from this point forward in the story they are no longer just ball players making a living, they are conspirators and frauds.
