Jose Mourinho, the man who dropped Rooney to the substitutes’ bench, Chris Smalling, the man who replaced him as captain, and even Claudio Ranieri, the manager whose side were dismantled by a revitalised, Rooney-less United, played down the significance of his absence.
Yet as he watched from the dugout as United got ruthless, Rooney must have known that while Saturday’s events might not have meant the ‘end of an era’, as some observers claim, they did represent the clearest threat ever to his position as a mainstay of the club.
“Regardless of whatever the situation is, whatever game, whether he is on the bench or playing or whatever, he is always that same type of character and that’s why he is England’s main man and our main man,” said Smalling, who had opened the scoring in a 4-1 win.
Since joining United 12 years ago as a teenager, Rooney has been a marquee figure; a man to be relied upon in the biggest moments.
If Mourinho’s selection on Saturday did not spell the end of his United career, it certainly suggested a change of role.
Without their out-of-form leader, United looked quicker, more incisive, and better balanced as the Premier League champions were embarrassed by a 20-minute spell of chaos.
And the men who filled Rooney’s many possible positions all made excellent cases for keeping him on the bench.
At centre-forward, a slot where Rooney has enjoyed success, Zlatan Ibrahimovic marshalled United’s attacking play expertly.
In midfield, where his career had looked to be heading, Ander Herrera, Paul Pogba, and Juan Mata set a tempo that has been lacking too often of late.
And out wide, where Rooney operated in a brief, late cameo, Marcus Rashford and Jesse Lingard offered a pleasing injection of pace and energy.
On the sidelines, Rooney cheered each goal, encouraged his team-mates, and smiled alongside Michael Carrick, a friend who has accepted a regime of ‘restricted duties’ in the twilight of his career in preference to seeking a bigger role on a smaller stage.
Whether Rooney can embrace a similar shift might well determine whether he can fulfil his ambition of ending his career with United.
“He’s our captain and he’s one of our main players,” said Smalling, after both Mourinho and Ranieri had explained away Rooney’s omission as a simple case of rotation.
“There’s no doubt that he’s got a lot to offer.
“He was the same before the game when we’re all getting ready. He is often one of the most vocal and he was the same.
“Even when there’s games we play in the League Cup and we change the whole team, he’s still the same, in the changing room talking. That’s something that will never change with Wayne.
“He’s a very experienced guy and he’s played that many games that I think it’ll only be a matter of time before he’s back in there and firing again because he’s quality.”
Smalling’s words of encouragement were predictable and yet, from the moment he headed United in front on 22 minutes, United took apart Leicester with a swagger rarely seen at Old Trafford since the departure of Alex Ferguson.
They were aided and abetted by a shocking defensive display from Leicester, who have now conceded four goals on three occasions this season and have already lost the same number of league games — three — as in the whole of last season’s fairytale title-winning campaign.
But while Smalling’s header from a Daley Blind corner was one of three goals from set-pieces, the brilliant second, finished by Mata, was more illustrative of United’s dominance.
Eight minutes before half-time, Herrera, Mata and Pogba constructed a slick build-up and Lingard’s neat lay-off allowed Mata to crash home a shot.
Leicester then imploded and United wrapped up the win before half-time, Rashford poking home from a short corner routine before Pogba headed in from another Blind delivery.
Leicester improved after the break and Demarai Gray, a half-time substitute, restored a little pride with the best goal of the day, curling a brilliant shot past David De Gea and into the top corner from 25 yards.
Still, though, it was a grim day for Leicester, whose defender Danny Simpson hinted a clampdown on grappling had hampered the Foxes’ set-piece defending.
“The way it was last season, I thought we were very good at defending set pieces and we made it tough for the opponents,” he said. “You have been doing that for all your career and suddenly you have got to change it, but it’s the same for everyone, it’s something we have got to work on and look at.”
De Gea 6; Valencia 6, Bailly 6, Smalling 6, Blind 7; Herrera 8; Lingard 7 (Carrick 78), Mata 8 (Young 87), Pogba 8, Rashford 7 (Rooney 83); Ibrahimovic 7.
Rojo, Romero, Fosu-Mensah, Fellaini.
Zieler 5; Simpson 5, Morgan 5, Huth 5, Fuchs 5; Mahrez 4 (King HT, 6), Drinkwater 6, Amartey 4, Albrighton 5 (Schlupp 62, 5); Slimani 4, Vardy 5 (Gray HT, 7).
Hernandez, Hamer, Okazaki, Ulloa.