Right from the start, Jamaal Lascelles could see that something wasn’t quite right. As the opening minutes played out at St James’s Park, Lascelles noticed from his position at the heart of the Newcastle defence that Manchester United, and in particular Chris Smalling and Phil Jones, were looking uncomfortable on the ball.

“First-half, they were making a lot of mistakes, giving the ball away,” he remembered. “I think it was down to our pressing, being aggressive and on the front foot. And obviously, they didn’t like it. I could see their centre-halves on the ball, and didn’t know what to do with it. I don’t think they were at it from the start. A lot of their players were missing.”

Though United gradually came into the game either side of half-time, they never truly settled, and Matt Ritchie’s second-half goal ended up consigning them to a 1-0 defeat. “I don’t think United turned up today,” Lascelles said. “When you play against Arsenal and Manchester City, you can really see their quality. One mistake or a lack of concentration, and a goal will go in. Today, we just wanted it a lot more.”

You know you have had a bad day at the office when you are being compared unfavourably to Arsenal in terms of concentration. But it was a curiously inert United that went down at St James’ Park on Sunday, one that only occasionally displayed the required intensity. While Newcastle played like a team who knew what they were doing, United did not. “We weren’t at the races,” admitted Phil Jones. “We weren’t good enough, it’s as simple as that.”

Partly, of course, United failed to show up at the party because Newcastle refused to invite them. And before we move on to United’s aches and pains, we should take a moment to pay tribute to Rafa Benitez for turning over United’s eye-wateringly expensive XI with a side barely good enough – on paper – to stay in the division.

For all their travails up front, and still no Newcastle player has scored five Premier League goals this season, Benitez has put together a teak-tough defence, the meanest of any side outside the top seven. They are well organised, commanding in the air, composed in possession. Benitez has even turned DeAndre Yedlin into a viable Premier League defender, an achievement that may ultimately rival the Miracle of Istanbul as his greatest coaching triumph.

And of course, Newcastle are fighting for their lives, which is another clear distinction between these two sides. Perhaps the unique dynamic at the top of the Premier League may be contributing to United’s indifferent form of late. They may be in second place, theoretically at the head of the chasing pack, but so far off Manchester City’s lead that they are still essentially looking over their shoulders. In effect, United are labouring under the psychological pressure of leading, without the kudos of actually being on top.

Phil Jones struggled on the ball at St James' Park ( Getty )

All of which feeds into the wider question that looms over the next three months: what, exactly, are United playing for? What would Jose Mourinho see as a satisfactory return for this season’s efforts? Second place? Secure a top-four slot and then have a dart at the FA Cup and Champions League? Nobody seems all that sure, and in a way that is the sort of eerie uncertainty that characterises United as a club at the moment: without a clear objective, or a clear style of play with which to achieve it, or a clear tactical blueprint around which to build it.

The arrival of Alexis Sanchez has fundamentally changed the look and feel of this United side. The Chilean was his busy, mercurial self against Newcastle, a team he has never scored against, gusting in off the left wing and missing United’s best chance of the game. Anthony Martial was shunted out to the right, a position that has never suited him, and with Sanchez driving into the centre, Romelu Lukaku was often shoved into deeper areas, from where he actually linked play reasonably well.

Yet the balance still feels all wrong, with the well-grooved attacking combinations that have been working all season now requiring recalibration. Such is Sanchez’s individual talent, of course, that he will always require a little indulgence. But since his arrival, United have now scored exactly twice in 270 league minutes. Even good dancers need a few waltzes to get to know each other.

Meanwhile, it is still not entirely clear where all this leaves Paul Pogba, who was substituted after an unhappy hour. In his favoured three-man midfield, Pogba would have the freedom to drive at the defence from deep, unfold his full and exquisite passing range, take on the spectacular long shots from which he scored so many for Juventus.

Yet just as forwards rely on service from the midfield, creative midfielders rely on service from their back four. Time and again – and evidently under instructions – Smalling and Jones would spread the ball straight to the flanks, even as Pogba dropped deeper and deeper to try and get it. Between them, Smalling and Jones made just six passes to Pogba all game, against 35 to their full-backs. Pogba could certainly raise his game a level or two, but he is being asked to perform a curious function that football’s many tactical evolutions have somehow overlooked: namely, to be a playmaker without the ball.