All good things must end. A curtain falls on every Shakespeare performance. A crescendo ushers the hush of every symphony's orchestra. The end credits roll on every film.
And even the greatest manager in the modern era will call time on his career, and as the great man celebrates his 25th year at the club that made him a legend, we all know that the end is coming sooner rather than later. There are, after all, no precedents for UEFA Champions League-winning octogenarians.
But a managing career that has been at times a Shakespearean tale of intrigue and tragedies that has been symphonic in its triumphs and cinematic in its scope began more humbly than it can possibly end. Twenty-five years ago, a young Scotsman named Alex Ferguson arrived at Manchester United to find a team in disarray. But while said team was burdened with expectations it was incapable of reaching, the new manager had no such pressure.
Win, yes. But this was a team without a sniff of a chance at knocking Liverpool of its (bleeping) perch, and thus was Ferguson given an opportunity to craft his team, his vision, in relative peace. At first, anyway.
Twenty-five years later, the story at the club is completely different. The young Scotsman is now "Sir Alex," the giant colossus of English football who has left Liverpool's perch well and truly abandoned. He has created a mentality where winning everything is not only expected, it is a life philosophy. Manchester United is now a club poised for greatness each year as established talent cycles out to allow new blood into the fold, learning from each other in a symbiotic relationship of excellence.
It is an empire presided over by a man who has seen French, Portuguese and Spanish pretenders to the managerial throne come and go.
And it is into this man's shadow that the next United manager will have to begin his career.
The skyrocketing expectations, the history of winning, the new challenges of Manchester City, Chelsea, Liverpool and Arsenal...it will take a special man to succeed in this job with Sir Alex watching closely.
Here are my top 10 candidates to take on that challenge, with varying degrees of probability mixed with hopefulness, of course.