Pep Guardiola sent Mikel Arteta a message about bottle at Wembley.
If he’d sent a warning - a message in a bottle, if you like - ahead of this week’s Judgement Day at the Etihad, it would have been spelled out in large letters. And it would have read as follows: That Manchester City are primed, ready and waiting - as they showed just how to handle pressure at Wembley.
This scoreline was emphatic. It didn’t need to be. At the final whistle, it just needed to be in favour of those wearing sky blue. But if the treble was to be kept alive, this was a hurdle they needed to overcome.
The Blades were tricky, stubborn opponents, high on confidence looking to cash in on a fatigued squad that had been pushed to its limits. But, unlike Arsenal, who faced bottom-placed Southampton at home on Friday with the chance to turn the screw, this dominant display showed that Manchester City are made of the right stuff.
The Gunners have come under the pump in the past few weeks and, one by one, the wheels are falling off. The memo they are sending out to the world is that their squad cannot cope with the loss of key players such as William Saliba and Oleksandr Zinchenko.
Cracks have started to appear. It’s rubbed off on others.
All of a sudden, Aaron Ramsdale looks shaky. Goals are being given away at a rate of knots. Five this week - in two matches against relegation-threatened sides.
The result is that we have arrived at the business end of the campaign - and Arsenal are falling away.
Not Manchester City. Oh no.
They too faced a team in the drop zone last week against Leicester City and were three goals up inside 25 minutes. This was done and dusted just after the hour after Riyad Mahrez unexpectedly wrote himself into FA Cup folklore by grabbing a hat-trick in 23 minutes.
Leicester? Tick. Bayern Munich. Big tick. And Sheffield United. Tick.
What makes this even more impressive is that the stakes are higher for them. Everyone expects they’ll win - until the season reaches an end. There is no margin for error. Defeat in any game this week could have spelled disaster on three fronts for Guardiola.
Yet he and his men emerged unscathed. Still with the very real possibility that a treble - feted as a once-in-a-lifetime achievement by Manchester United - might well not be.
Guardiola was given a far easier pass than 12 months ago, when he was faced with similar issues. Back then, Liverpool stood in his way. That semi-final came off the back of a tough, uncompromising night in Madrid against Atletico.
He swapped seven of his team after that scrap against Diego Simeone’s mob and was only one shy of repeating those changes for this. But although Paul Heckingbottom’s men were game, they were never really in the game.
Ederson was one of the men given the afternoon off by Guardiola, but his replacement Stefan Moreno won’t remember too much about the afternoon - all he did was gaze around the arena.
And that’s the way it should be when top teams chase glory.
Sheffield United gave it a go - their focus is on their own day of destiny on the same night when the Premier League title-chasers meet. West Brom visit Bramall Lane. Automatic promotion is at stake. They will rouse themselves again.
And this won’t have dented the confidence too much. Those hardy supporters who travelled to north London more in hope than expectation will ensure the atmosphere remains upbeat.
Who knows? They might even be able to crack open a bottle or two of their own at the final whistle.
As for Manchester City, the dream goes on. A shipment of the famous green glassware full of bubbles looks certain to be en route to east Manchester at some stage.
Quite how many they’ll need, though, remains to be seen.
