According to an ESPN article by Chris Low, Nick Saban made a phone call to another sitting head coach the morning after his retirement announcement.
Nick Saban never made a public declaration on who he would like to see succeed him as the Alabama head coach. There was no coach-in-waiting. There was no real time to plan. His retirement 19 months ago was abrupt and unexpected. One day, he was the Tide's head coach; the next, he was not.
Alabama Athletic Director Greg Byrne had a plan and executed it with near flawless precision.