By Conor Orr Teams, owners, scouts and executives will try to implement what the NFL’s greatest player brought to the league, but Tom Brady’s retirement will still leave a lasting void. What happens to a sport when its greatest player retires? For athletes who leave the game, the cruel realities of their current situations set in. Life moves on. The game moves on. The locker room gets populated with new people, new attitudes, new catchphrases, new postgame dances and cafeteria inside jokes. Most jersey numbers get re-worn. Games are won without them. The frantic, beautiful sideline conversatio…