Ruben Amorim has admitted ­Manchester United’s players were ­nervous on Sunday during their 3-0 defeat by Bournemouth, which left the club 13th and in the bottom half on ­Christmas Day for the first time since 1989.

The defeat was a second in a row by that scoreline at home against Bournemouth, almost exactly a year after the first. United went behind to the seventh goal they have conceded in the past six games at a set play.

Amorim said: “This game was hard on us. We suffered again on set pieces and we were a little bit nervous – also the stadium at the beginning of the game, I felt it … It’s a lot of mental [nervousness]: you can feel it not just with the players, the fans too.

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“I felt it from the first minute, there’s a lot of anxiety; that’s normal because of the context [needing to win] and it’s really disappointing. It’s a tough moment but we have to face it and prepare for the next game.”

Dean Huijsen’s 29th-minute opener derived from a free-kick at which he was left unmarked. This occurred after United were drilled before kick-off by the assistant coach Carlos Fernandes in defending set pieces. Amorim was asked whether he might replace ­Fernandes in coaching set pieces.

“It is my responsibility to coach them, not Carlos – it is all on me,” he said. “Of course we want to improve. In this moment, everything is so much harder – a club like Manches­ter United to lose 3-0 at home, it’s really tough for everybody. And of course the fans are really disappointed and tired.

“You can feel it in the stadium and I understand that, but we have to face it. We know what to do. We have to improve set pieces. I think we are not giving the ball away as much as we did. We control the game better, we don’t concede a lot of spaces, transitions, we ­control very well against one team who score 60% of their goals when the ball is in [the opponents’] half.”

But Bournemouth’s second and third goals came in quick succession, Justin Kluivert’s 61st-minute ­penalty being followed by Antoine Semenyo’s strike two minutes later. Amorim referenced his players’ reaction to going 2-0 down. “Keep the ball for a moment and not try to score two goals right away. It’s a really tough moment and we have to understand that – what the players are thinking in that moment … We have to address that.”