It was plainly too good to be true. Or to last. There were 82 seconds on the stadium clock when the Ruben Amorim era at Manchester United was jumpstarted. The new manager had put his faith in Marcus Rashford in the No 9 role and it was United’s great enigma who put them in front. Rashford charged about in the early running, a point to prove.

And yet it was the prompt for a slow retreat by United for the remainder of the first half. The structure was different, United set up in Amorim’s trademark 3-4-2-1, but the players were the same, along with plenty of the frustrations and faultlines from Erik ten Hag’s tenure. Control proved elusive. As it did so often under Ten Hag.

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Ipswich were the better team before the interval and the excellent Omari Hutchinson got the goal they deserved before the end of it with a shot from distance that took a deflection off Noussair Mazraoui. Ipswich had won for the first time this season at Tottenham before the international break. This was in point-gained territory for them.

Not so for United. After all of the talking and, goodness gracious, there has been some talking, Amorim’s arrival feeling like the coming of the messiah, it was time for United to fire some optimism. They could not do it. They were a bit better in the second period but not hugely and it looked as though the players had too much to process in terms of instructions. It all became stilted. Then again, as everyone knows, least of all Amorim, it will take time. He has only had two training sessions with the full squad.

United had risen one place in the table on Saturday without playing – evidence, the club’s support hoped, of Amorim’s magic – and there was always going to be a spotlight on his first starting XI. Amorim talked on Friday about the need to “adapt some players” because he did not have the right profiles for his three-at-the-back system and there were a few square pegs in round holes, especially the left-footed attacking midfielder Amad Diallo at right wing-back.

Amorim did not have three fit specialist centre-halves – there were four out with injuries – and so it was the full-back, Mazraoui, on the right of the back three. Casemiro and Christian Eriksen in central midfield did not scream revolution. Or pace and intensity.

Roy Keane became embroiled in an angry exchange with an Ipswich fan on Sunday. While off air for Sky Sports’ punditry team on the Portman Road pitch, Keane came in for abuse from a supporter who barracked him as ‘a better pundit than manager’. Keane, who was Ipswich manager from 2009 to 2011, stormed over to the fan in the stands and repeatedly shouted that they should ‘discuss it in the car park’.

Talk about the dream start, an element of vindication, because it was Diallo who made the goal. He moved smartly through the gears up the right wing and, having slipped a tackle from Jens Cajuste, his low cross was made to measure for Rashford. The travelling United fans had chorused Amorim’s name after 30 seconds. They belted it out on loop for the next couple of minutes.

Ipswich stabilised. It was clear that Hutchinson had the beating of Casemiro and Jonny Evans, who played on the left of United’s back three. Hutchinson, in the right-sided No 10 role, was sharp with his turns and very quick.

Amorim was a presence at the edge of his technical area. This is what coaching on the hoof looks like and it had to alarm him that United sank deeper. They looked to hurt Ipswich with long diagonal passes but it was the home team that took a grip on the midfield.

The equaliser had been advertised, André Onana busy in the United goal. He had pushed away a first-time hit from Sammie Szmodics in the 11th minute but the big save came in the countdown to half-time. Leif Davis stepped inside Diallo and he waited for the move of Liam Delap, putting the ball on a plate for him. Eight yards out, Delap put his foot through it only for Onana to throw out a big right hand, Peter Schmeichel-style, to block.

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United’s reprieve did not last long. Inevitably, it was Hutchinson, checking away from Casemiro on the right-hand edge of the area, quick feet to the fore. His curler flicked off Mazraoui’s head to deceive Onana on its way in.

United pressed more on to the front foot after the restart, although they might have conceded when Delap tricked away from Matthijs de Ligt and surged through the middle. De Ligt looked awfully slow. Delap went right to Wes Burns and sprinted to meet the cross, his spectacular flick kept out by Onana.

Alejandro Garnacho had worked Arijanet Muric from a tight angle at the start of the second half. And there was the moment on 54 minutes when he led a break with Rashford available inside for the pass, Cajuste the only Ipswich defender. Garnacho looked for Rashford; Cajuste made the crucial interception.

Amorim searched for the solution. He got Luke Shaw on at left centre-half for his first football of the season, ordering him to stay close to Hutchinson. Manuel Ugarte replaced Casemiro. It was Rasmus Højlund for Rashford and Joshua Zirkzee was introduced in the right-sided No 10 role, Bruno Fernandes dropping back into midfield. There was a late sighting of Mason Mount, who came on for Garnacho.

United could not make it happen. Fernandes curled a free-kick inches wide and it might have been worse for them if the Ipswich substitute, Conor Chaplin, had shot either side of Onana from a cross by another replacement, Jack Clarke. Not for the first time, Onana stood tall.