For the first time in over 26 years, Manchester United fans are preparing to adjust to the sight of a new figure settling into the manager's seat in the dug-out at Old Trafford.
When Alex Ferguson replaced Ron Atkinson in November 1986, he was the latest in a long line of managers bidding to return the club to the heights they had last enjoyed under Matt Busby in the late 1960s.
Wilf McGuinness, Frank O'Farrell, Tommy Docherty, Dave Sexton and Atkinson all came and went, with varying degrees of success, but Ferguson's retirement, which he announced on Wednesday, leaves a yawning void.
The United manager's job has always been one of the most high-profile coaching roles in world football, but Ferguson's departure leaves his successor -- tipped to be Everton's David Moyes -- facing an unenviable set of quandaries.
The man who steps into the vacuum Ferguson's departure has created will find comparisons with his feted predecessor awaiting at every turn, and there will be next to no time for a bedding-in period.
Such are the heights to which Ferguson has elevated the club that they cannot afford the backwards steps that a newcomer at another team might be granted.
United have not finished outside the top three since 1991. They have not failed to qualify for the Champions League since 1995. Since lifting the 1990 FA Cup, they have finished a season without at least one piece of major silverware on only three occasions.
On a more optimistic note, the incoming manager could not wish to inherit a more minutely calibrated winning machine.
The modern United seethe with a will to win instilled by Ferguson, and his successor will find an organism geared to success right down to the height of the grass at the club's world-leading Carrington training facility.
He will also inherit a team of champions, who romped to this season's Premier League title with almost disdainful ease.
More importantly, he will find a squad geared for sustained success over the years ahead.
The current squad brims with young players such as Phil Jones, Tom Cleverley and Danny Welbeck who are yet to reach their peak, and Ferguson himself believes his template for victory will not need much adjusting.
"The quality of this league-winning squad, and the balance of ages within it, bodes well for continued success at the highest level, whilst the structure of the youth set-up will ensure that the long-term future of the club remains a bright one," he said.
Outgoing chief executive David Gill said United would appoint a manager willing to get involved, like Ferguson and Busby, with "all aspects of the club", rather than a European-style coach.
Should Ferguson's successor wish to make a mark in the transfer market, he is likely to find funds at his disposal.
United have not broken any transfer records since Dimitar Berbatov arrived from Tottenham Hotspur for Â£30.75 million ($46.9 million, 35.7 million euros) in September 2008, but their most recent financial results revealed a rise in revenue of Â£91.7 million.
Having recently announced a glut of new sponsorship link-ups, predominantly in Asia, United's marketing operation continues to grow, and incoming chief executive Ed Woodward has vowed that some of that largesse will go towards improving the squad via the transfer market.
Globally, the squad appears to require little work, although neutral observers have long decried the absence of a creative driving force in United's central midfield.
The new man must also address Wayne Rooney's position at the club, amid speculation about the England striker's long-term future.
Although he is stepping down as manager, Ferguson is due to remain at the club in as-yet unspecified directorial role.
He will remember more than anyone the inadvertent damage that Busby caused by lingering on behind the scenes after leaving the dug-out, but after over 26 years in the role, he, too, may find it difficult to let go.