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Perhaps the biggest reason for Sir Alex's sustained success at the helm of Manchester United was stability.
There were down years, of course, but there were always key figures both in the dressing room and in the backroom to uphold the club's winning traditions.
With Sir Alex's exit, coaching stalwarts Rene Meulensteen, Mike Phelan and Eric Steele have also followed suit.
David Moyes has brought with him his Everton assistants Steve Round, Chris Woods and Jimmy Lumsden, names that are mostly unfamiliar to United fans.
The new manager must be able to trust the men he works with day-to-day, but a revolution is not needed at a club coming off a dominant domestic campaign.
There must be United men working backstage, men who understand the way the club works.
The appointment of a Phil Neville, Ryan Giggs (as a player-coach) or Paul Scholes would greatly help the transition.
What other concerns do you have about the upcoming season?