Harry Maguire was at a loss to explain Manchester United's struggles against opposition in the bottom half of the table and manager Ole Gunnar Solskjaer was similarly nonplussed after Sunday's 2-0 defeat at Watford.
United produced another insipid performance at Vicarage Road, as they struggled to create chances before Paul Pogba's 64th-minute introduction, but by that point they were already two down.
A David de Gea howler allowed Ismaila Sarr to open the scoring early in the second half and Troy Deeney made it 2-0 from the spot after Aaron Wan-Bissaka tripped the Watford winger.
United have made a habit of dropping points against teams in the Premier League's lower reaches, with the Red Devils winning 73 per cent of league matches under Solskjaer in which they have had less possession than their opponents, compared to just 36 per cent when they have had more of the ball.
But when asked about such struggles after the match, neither Maguire nor Solskjaer seemed to have any idea what the reason might be.
"It's something we can't really put our finger on," Maguire told Sky Sports. "We're working hard in training and that's all we can do, coming into these games prepared as well as we do for the likes of Manchester City away.
"It's disappointing. I always think when you play these games against the so-called lower opposition in the table that the first goal is crucial, so big, and we had chances to get it."
Solskjaer was similarly uncertain, instead focusing on the specific issues he identified in Sunday's defeat.
When asked about the discrepancy in United's form, Solskjaer said: "Well, you've got to earn every single point, every inch on the pitch, and we didn't deserve that.
"We were too slow, too many touches in the first half, too many passes that went astray and we didn't create enough chances.
"Obviously, we could have had one or two goals ourselves, it's about taking them when we get them. We could've scored the first.
"I can talk about it all day long – we didn't [take our chances] and now we have to face the fact that we've got two games against Newcastle [United] and Burnley coming up that we've got to improve on."
United are next in action against Steve Bruce's Newcastle at Old Trafford on Boxing Day.