The Red Devils were beaten 3-0 by Bournemouth at Old Trafford for the second successive season.
Dean Huijsen, Justin Kluivert and Antoine Semenyo got the goals to condemn Ruben Amorim’s team to Christmas in the bottom half of the table.
It is now the first time they are in that position in the club’s history, or since the formation of the Premier League at least.
United have also conceded 17 set-piece goals in 2024 in the Premier League, another record for the club.
Post-game, Amorim told told Sky Sports: "It's hard. In this context, it's hard to push for two or three wins. We're trying. But this game was hard on us.
"Without any situation, we suffered again at set-pieces. We were a little bit nervous, the stadium.
"We controlled the rest of the first half with some clear chances, and then in the second with the penalty and then another goal is really hard on everyone here.
"In this kind of moment, everything is hard on us. The set-pieces, the penalty, then we want to score again but we are too nervous. We have to fight this.
"We tried to score but in the end, it was a tough match in a tough situation. We need to move on."