Ten Hag's side failed to come close to the performance levels of Wednesday's win over Chelsea as Bournemouth inflicted the club's heaviest-ever home defeat by a team sitting in the bottom half of the Premier League.

Dominic Solanke, Philip Billing and Marcos Senesi were on target for the visitors, condemning the hosts to a seventh Premier League loss of the season and prompting loud boos from the home fans.

Having lost further ground in the race for the top four, Ten Hag rued his side's inconsistency and lack of focus afterwards.

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"That is always the question," he said when asked how to explain such a poor performance only three days after beating Chelsea. "As a coach, you are questioning that after what happened.

"We started very poorly. There was I think a big difference, I think, to Chelsea when we started the game very well and we were very aggressive and very focused. Today, we were not."

Of Bournemouth's second goal, scored soon after Bruno Fernandes had seen a penalty appeal turned down and Diogo Dalot had fired a shot into the side netting, Ten Hag said: "We got a shot. Penalty, no penalty. And then straight after that we concede a goal and that should never have happened."

All three Bournemouth goals stemmed from United sloppiness, with the opener, scored by Solanke in the fifth minute, setting the tone for a shambolic defensive performance as Lewis Cook cut out Fernandes' poor pass before breezing past Sofyan Amrabat.

"It was our fault in the build-up," said Ten Hag. "We knew they were aggressive in the pressing. You shouldn't give away the ball so easily. Then, defending in transition, we gave them too much space.

"It's a good goal from their side, but from our side you can't be starting like this. You have to get a better position and it all has to do with focusing."

Ten Hag viewed the second goal as decisive.

"I think in the first half already we had a good tempo, also good attacks," he said. "We are in control of the game.

"We came to the box but we didn't create so much in the box. We continued in the second half, but the breakdown was the second goal.

"I refer to that game from Chelsea. You have to be at your best in every game. That demands a lot of energy, starting with the right focus. When you start like we did, you can't do it. You get killed.

"It was a good opponent, they played very lively and very dynamic. So, credit to them, but we have to do things better.

"You have to deliver every day. That demands a mentality, so you have to bring it. We have to change that."

Sherwood: They threw the towel in

Speaking on Soccer Saturday, Tim Sherwood accused Manchester United's players of giving up in the second half and said he sees little chance of them finishing in the top four this season.

"I think the performances have been as bad as this, but they've got away with it," said Sherwood. "They improved against Chelsea because they didn't have to take the game to the opposition. They could play counter-attack football.

"There's nothing wrong with being a counter-attacking side but when a team wants to sit back, you have to find a way of opening them up. They are devoid of anyone with any imagination or creativity apart from Bruno.

"But if you have Bruno in your team, he is not going to work back. Amrabat is left on his own in there and hasn't got the legs.

"Credit to Bournemouth. They had a game plan and pounced on it and were clinical in their finishing. But very rarely was I off my chair thinking Manchester United must score here. Bournemouth were quite comfortable.

"We're talking about a team in 16th going away from home to Old Trafford. I'm within my rights to think Manchester United, with world-class players and the money they've spent, should be able to break them down and score.

"But they got worse. In the second half, they came out and it looked like they had thrown the towel in, which is unfortunate for their fans watching on.

"At the moment, I cannot see Manchester United getting into the top four this season with performances like that."