When Jose Mourinho last met Leicester City, it was the beginning. When he last faced them in a Premier League match, it was the end.
It prompts the question if this is the end of the beginning, even if it is premature to brand it the beginning of the end.
Mourinho may still be scarred by Chelsea's 2-1 defeat by Leicester in December; he was sacked three days later.
His first game for United was the 2-1 Community Shield triumph over the reigning champions.
Cue the kind of impressive start that Mourinho tends to make, only for the honeymoon period to end abruptly.
After three successive defeats, mitigated only by a 3-1 away win over League One side Northampton in the League Cup third round in midweek, United need to get back on track.
They must resemble a classic Mourinho team - clinical, forceful, efficient - just as he has to be at his decisive best.
The Portuguese has been curiously uncertain of himself, fielding eight different players on the wings in the last two weeks, and has seen his thinking exposed in the spine of the side.
While it was against limited opponents, the Northampton game illustrated that United require Marcus Rashford's presence on one flank, and not just because he adds much-needed pace and vibrancy, and the class of Michael Carrick and Ander Herrera in midfield.
Factor in Paul Pogba and Zlatan Ibrahimovic and it leaves Mourinho needing to rip up his original blueprint.
Marouane Fellaini and Wayne Rooney have been Premier League ever-presents. Yet the Belgian is no natural holding midfielder while the captain has been increasingly awful.
As Pogba would benefit from a switch to 4-3-3, the No. 10 role should be obsolete. Rooney ought to be dropped.
Certainly, with Leicester notable for their speed, United cannot afford to field another slow side.
Instead, with Leicester likely to start four men who played 120 minutes in Tuesday's 4-2 League Cup defeat by Chelsea, they should look to secure a physical advantage.
United can expect to have more of the ball, but that cannot be an excuse for ponderous possession. Leicester look more fragile defensively since N'Golo Kante's sale.
The quick movement of players into the area around and behind Ibrahimovic could expose one-paced centre-backs.
At the other end, Luke Shaw, criticised by Mourinho, must be alert against Riyad Mahrez. Chris Smalling's height and speed mean he should get the nod over Daley Blind to cope with Islam Slimani's aerial threat and Jamie Vardy's electric acceleration.
After their recent slump, this is a test of United's mental strength as well as their footballing ability.
It is an examination of Mourinho: Can he galvanise players, instead of alienating them, as he did at Chelsea?
And it is a chance to make a statement by seeing off the champions and by proving United's troubled last fortnight was merely a blip.
MANCHESTER UNITED V LEICESTER
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