Erik ten Hag will have to discard the buzzword Manchester United’s manager came into this game citing. “Momentum” is now obliterated after a defeat that ends a run of victories at two as, yet again, his men must regroup, this time for Galatasaray’s visit on Tuesday in the Champions League.

United have lost four of their seven first league games. This last occurred in 1989-90, the season in which the infamous “Ta Ra Fergie” banner was held up at a match in December to demand that Alex Ferguson be sacked. The Scot was not, of course, but Ten Hag will know he has to stem the serial losses or his job will be in danger; his team have scored a paltry seven times and have a goal difference of minus four.

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At the close there were boos. “I understand,” the Dutchman said. “We played at home and we played Crystal Palace, who we have to beat, with all respect. I know every game in the Premier League is difficult, you have to play your best and I understand fans expect their best.”

On Friday the manager named Alejandro Garnacho as a player who was not in the team as a result of not performing. Yet United were suddenly an electric proposition when the rocket-booted winger came on in the second half. In one moment of devilry Garnacho bamboozled Crystal Palace along their right byline, his cross ricocheting off two defenders as the ball threatened to go anywhere – including past Sam Johnstone for the equaliser.

But no. Joachim Andersen’s smash-and-grab strike in the opening half allowed Palace revenge for Tuesday’s 3-0 Carabao Cup defeat despite United dominating the closing phase; in added time the substitute Donny van de Beek nodded the ball to Garnacho, who had his shot saved by the impressive Johnstone from close in.

Garnacho had taken over on the left from a tepid Marcus Rashford, who was replaced by Christian Eriksen a little after the youngster’s introduction. Rashford has only one goal this season and Ten Hag accepted he is misfiring.

“He knows he can do better and I am sure it will come,” said the manager. “He works hard. He will net and it will come but it is not going to be automatic. The team has to invest a lot around him. Today the decision-making was not good enough.”

Ten Hag also admitted he has to work to stave off this being a long campaign of taking one step forward and then two steps back. “Of course that is the concern and we have to be more consistent,” he said. “The demand is we get a row of wins and we have to do better than we do now. I can give you reasons but you will explain it as an excuse and there are no excuses – we need to win.”

Asked if United are a soft touch before their own crowd, Ten Hag demurred – but only just. “We have now lost two games in a row here in the Premier League but I won’t set that conclusion now,” he said. “We have to do better, that is definitely the case, and we have to show it in our body language that Old Trafford is a fortress and you can’t get anything here and the only thing you can go away from here with is a loss.”

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For Roy Hodgson victory was just dandy, and makes him the first manager in Premier League history to be undefeated here in five consecutive games – four with Palace and once with Watford. “I am happy about that,” he said. “What I am most happy about is the way the team played and so pleased for the players – it’s not easy coming here for the second time in a few days and give that performance and work so hard for 90 minutes. I am not certain I can tell you about the other games before though I am pretty sure I would have been delighted about those too.”

United’s concession came via self-destructive defending. Eberechi Eze hit over a free-kick from the right and those in red allowed the ball to go all the way to Andersen, with Rasmus Højlund the chief culprit for missing a header. Andersen hit a sweet finish past André Onana into the goalkeeper’s left corner.