The Boston Celtics had an extreme makeover this summer, completely transforming the roster, and in the process quietly said goodbye to Torrey Craig.
There is no team announcement when the internal decision is made not to retain a player.
That is done implicitly when a player signs a contract with another team; if you are employed by a new franchise you obviously are not returning to the Celtics. It is less obvious when the team has decided to head in a new direction, but the player is merely a free agent with the ability to return at any moment.