This was jubilation for Bournemouth and a crimson embarrassment for Manchester United which would have been worse had Dango Ouattara’s late strike not been ruled out, via VAR, because of the player’s handball. But make no mistake, Erik ten Hag’s team were a rabble reminiscent of the United of the dog days under his predecessor, Ole Gunnar Solskjær, and so at the final whistle the boos that greeted them were no surprise.

Bournemouth’s second goal, in the 68th minute, killed off Ten Hag’s side en route to a first ever victory at Old Trafford. A loose Luke Shaw pass was intercepted by the Cherries, who motored upfield. Dominic Solanke fed Marcus Tavernier on the left and, when he lifted the ball in, up rose substitute Philip Billing to crash in a memorable header.

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Worse, if possible, was to follow as Ten Hag’s ragtag bunch conceded another aerial goal. This time Marcos Senesi’s header beat André Onana, to the United goalkeeper’s left. Some home supporters left immediately and the travelling congregation sang “Hey Iraola” about their adored manager, Andoni Iraola. All of this followed Solanke’s fifth-minute finish – he might have had another towards the end but fluffed the attempt – and meant by the final whistle Bournemouth had taken their total tally here from five to eight in a seventh league visit.

The result leaves United with a goal difference of minus three from nine wins and seven defeats and reinforces the sense of this Ten Hag side as an enigma. The manager himself might privately admit that he has little clue which one will turn up on any match day. Might it be the slick unit that administered a 2-1 defeat of Chelsea here on Wednesday? Or the insipid sleepwalkers of this afternoon that never convinced from the moment Solanke turned in Lewis Cook’s cross from the right?

Two moments, seconds into the second half, offered an apt picture of how United performed versus this resurgent Bournemouth. First, Solanke turned Shaw inside and out and went close to making it 2-0. Then, as United countered from this move, Anthony Martial sent Alejandro Garnacho zipping along the left and though sustained pressure and a Bruno Fernandes shot followed, this was blocked as a killer blow before goal was lacking.

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A little after this Ten Hag took off the ineffective Martial and introduced Rasmus Højlund. Yet nothing much changed. United struggled to create for their new No 9 to finally break his Premier League duck. A quick one-two with Fernandes engineered an opening but the Dane’s effort was mis-hit. Then came a quicksilver moment, perhaps United’s best: Diogo Dalot darted through from right-back and swapped passes with Antony but the shot hit the side-netting.

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After the bright performance and victory over Chelsea what United did not need was to be rocked five minutes in. Here, Scott McTominay turned from the two-goal hero of that win to chief culprit as, slumbering, he allowed Cook to mug him along the right. The midfielder trotted forward, rolled the ball in and the unmarked Solanke slid past Onana for a too simple opener.

It was hapless from Ten Hag’s men, for whom a step forward is too often followed by a retrograde one. In the pre-game briefings the manager cited the need to be consistent so this, as he stated afterwards, “annoyed”.

After a further scare for the home team – Tavernier’s headed goal was disallowed for Solanke’s offside at the latter’s initial header – they launched a sweeping move. Sergio Reguilón, in for Victor Lindelöf, burst through, curved the ball left to Garnacho, the winger roved in, but Iraola’s men escaped.

While Marcus Rashford again being left out was no surprise, Højlund not starting a second league game out of the past three was, Martial once more his replacement. The Frenchman has one Premier League goal this season and though this is more than the 20-year-old, Ten Hag’s decision was a puzzle. As is where, precisely, his team are heading. Yet while this bloody nose leaves United with 12 points from the last 18, for Bournemouth all is rosy as they have taken 13 points from the last 15. Next up for United is a trip to Liverpool, for which Fernandes is suspended after being booked.