The writers put in Tony's ankle injury during the fight with Jack because in real life Carlos Bernard injured his ankle. If you look carefully you can see Bernard limping slightly in earlier scenes before the on-screen fight gets his character's injury matched with the actor's injury. Bernard stated in an interview that the writers planned for the fight between Jack and Tony to be more elaborate and longer, but they had to cut it down when he was injured.
Brent Sexton (Frank Davies) and Michelle Forbes (Lynne Kresge) later played husband and wife on The Killing (2011).
In a 'blink and you'll miss it' moment at 32:36, when Mike says "it isn't" you can see what appears to be a tear running down Jude Ciccolella's cheek, it might be sweat, but he also appears to have watery eyes and a lump in his throat. In the next shot he's back to normal.