On a day when Marcus Rashford was finalising a loan move to Aston Villa, Ruben Amorim opted to drop his two remaining centre-forwards and instead stick a midfielder, who has spent most of the campaign playing as a No 6, in attack against Crystal Palace in the hope of finding a better route to goal. It felt like a punt, a leap of faith and, unsurprisingly, it did not work, Manchester United looking as toothless as ever as Palace condemned Amorim’s side to their fifth defeat in their last six home Premier League matches as another round of boos greeted the final whistle.

Jean-Philippe Mateta’s match-winning brace took his tally to six goals in his past five league outings, which is more than Rasmus Hojlund and Joshua Zirkzee have managed between them in the top flight this season, despite their combined £108 million price tag. So Amorim’s reluctance to start with either striker was, in a sense, understandable but, even for a manager struggling badly to find solutions to the current mess, the decision to use Kobbie Mainoo as a false nine felt an odd one and was abandoned with 20 minutes to go and his team 1-0 down.

Maybe things might have turned out differently had a deflected shot by Mainoo gone in and not hit a post early on but, three days after the success the England midfielder had when moved further forward into the No 10 role against FCSB in the Europa League, this was a position change too far. But then this is the situation United now find themselves in: Amorim feeling he has to resort to ever more desperate tactics as United’s rank failure to address a long-standing lack of goals starts to take on a life of its own.

Only four teams – including the bottom three – have scored fewer goals than United this term but this is not a new problem. United managed only 58 goals in Erik ten Hag’s debut season and one fewer in his second and are now scrambling to find a temporary stop-gap in the final 24 hours of the transfer window. And even then, the options being explored feel underwhelming: a teenager in Mathys Tel that Bayern Munich are happy to move on, who has no real pedigree of scoring goals, or Christopher Nkunku, the occasionally fit Chelsea player who is more attacking midfielder than out-and-out striker.

Maybe something else will materialise before Monday’s deadline but consider this: Nottingham Forest’s Chris Wood has scored as many goals in the Premier League this season (17) as United have at Old Trafford in 13 league matches, seven of which they have lost. The last time that happened was 131 years ago. So the idea of United doing nothing seems unthinkable. Amorim has now lost seven of his first 13 Premier League games since replacing Ten Hag in November, a miserable afternoon against Palace compounded by what the head coach fears is a serious knee injury to Lisandro Martínez, who went down awkwardly challenging Ismaïla Sarr in the 77th minute and left the field in tears on a stretcher.

With Luke Shaw due back very soon and left wing-back Patrick Dorgu, who was paraded before kick-off alongside another new signing, Ayden Heaven, now on board, maybe Martínez’s absence will not be quite as costly as it has proven in the past. Yet there are no certainties Shaw will stay fit and there may already be an unreasonable level of pressure on Dorgu, still only 20 and who has had just 18 months as a senior professional, to hit the ground running.

Palace love playing United. They have won three of their last four games against them and not conceded once in that time. The last time United failed to score against the same opponent in four league games running was Arsenal between 1981 and 1983. Oliver Glasner favours the same 3-4-2-1 formation as Amorim but the difference is Palace know how to execute it and took advantage when it counted. Eberechi Eze’s introduction off the bench brought fresh impetus and it was from his free-kick, after a needless challenge by Martínez on Sarr, that Maxence Lacroix thundered a header off the crossbar. Mateta – who would have given Palace a late first-half lead but for André Onana tipping his shot round a post – tapped home the rebound.

United had 11 corners to Palace’s none, 17 shots and 59 touches in the Palace penalty area – well over double their opponents’ total – but this team do not have a nose for goal. Bruno Fernandes and Manuel Ugarte forced good saves from Dean Henderson but they were the only two occasions in the game United troubled the Palace goalkeeper. Mainoo started brightly enough but faded and all around there are too many players lacking confidence and uncertain what to do. Palace’s second was an example of Glasner’s system working well, Daniel Muñoz beating the offside trap to race on to Sarr’s through ball to square for Mateta to score.