A former Manchester United club scout has derided the team's eye for talent by claiming that they let a 'top-class' youth prospect go for a minuscule fee - and labelling one of their newest signings a 'dud'.
Piotr Sadowski joined the Red Devils in 2017 as their Central European scout and only left after seven-and-a-half years combing the continent for major talents.
But Sadowski, most recently worked as part of Blackburn Rovers' scouting team, suggested that in recent years, mistakes had been made with regard to the club's policy of investing in the development of young players.
The scout labelled his former team 'lacking in courage' in their commitment to creating a pathway from youth sides to Ruben Amorim's first team, and named Real Madrid defender Alvaro Carreras as one of key departures Man United should rue.
'He came to Manchester United when he was probably 16 (in 2020),' Sadowski said of the Spanish star in an interview with Polish outlet Przeglad Sportowy. 'A very hard-working and ambitious boy, he learned the language quickly - I know because I met him personally.
'Initially, his career path was quite good. He was loaned to Preston, received good reviews, and (then) United gave up on him, selling him to Benfica for a small fee.'
Carreras this summer retuned to Madrid after starting his youth career at the Spanish giants, in a deal worth a reported £44million (€50 million).
The 22-year-old has since made 12 appearances under Xabi Alonso, scoring his debut goal for Los Blancos against Valencia at the start of this month.
The left back's move to the Spanish capital comes just three years after he was plying his trade for Preston North End, having been loaned to the Championship side, and then Granada, during his time at Man United.
'Carreras is a truly top-class player,' Sadowski continued. 'There's a good chance he'll become the best, or one of the best, left-backs in the world.
'He scored a beautiful goal recently against Valencia in La Liga. It was a huge mistake for United to let him go.
'Something is missing here and I think that something is United's lack of courage in investing in young players.'
20-year-old Kobbie Mainoo is the only academy player in Amorim's core squad this season, although the young star could yet be on his way out at Old Trafford after he is thought to have been keen for a move during the summer transfer window.
But although picking from Carrington's ranks is not Amorim's preferred managerial method, the Portuguese head coach has tempted a number of young stars to Manchester in the transfer market.
Among those signed this summer under the age of 25 were Benjamin Sesko (22), goalkeeper Senne Lammens (23), and left back Diego Leon (18).
Sadowski however was quick to scrutinise Patrick Dorgu, who joined the side last January at the age of 20.
Dorgu has made 10 appearances out of Man United's 11 in the Premier League this term, but Sadowski suggested that the Denmark international was somewhat of a an overpriced option in the side.
'Honestly, having recently worked at Blackburn Rovers and operating on a much lower transfer budget, I would have had no problem finding a few players of Dorgu's level for United, but for £25m, you could get four,' Sadowski continued.
'Now, United are wary of bringing in youngsters. Amorim was supposed to be the one to do this, but the results haven't been right, so he prefers to buy ready-made players.'
One player that Sadowski did stress that Amorim should take a chance on from Man United's academy is Harry Amass, who is currently on loan at Sheffield Wednesday.
Like Carreras, Amass is a left back, who has enjoyed 11 appearances in the Championship thus far this season, scoring his first goal for the Owls in his last outing against Southampton.