Ruben Amorim's desire to instil his style of play at Manchester United is being hampered by the club's academy teams' adherence to a tactical blueprint that doesn't align with his philosophy. Amorim acknowledges that United can't simply buy their way back to the top, especially after missing out on a £100million Champions League windfall following their defeat in the Europa League Final.

The Reds Devils' manager is prepared to uphold the Old Trafford tradition of promoting talent from United's highly productive youth set-up during his rebuild, a strategy he successfully implemented at Sporting. However, United's academy teams are rooted in a 4-3-3 system that Amorim doesn't subscribe to.

He believes this makes integrating young players into his senior squad even more challenging due to their formative training. Despite this, Old Trafford academy chiefs maintain they continue to develop footballers capable of adapting to any tactical demand - and Amorim has given first-team debuts this season to youngsters Harry Amass and Tyler Fredricson.

He also included promising talents such as Dan Armer, Jaydan Kamason, Godwill Kukonki, Tyler Fletcher, Sekou Kone, Shea Lacey, Jack Moorhouse and Jim Thwaites in United's squad for a post-season tour of the Far East.

However, there is a disconnect between the way United's age-group teams play and how Amorim sets up his senior side. He remains committed to a formation that utilises a three-man defence and requires wing-backs to provide attacking width.

Amorim, renowned for crafting an enviable coaching pedigree at Braga and Sporting, remained unwavering in his approach upon taking the reins at Manchester United. Despite a rocky start since his appointment in November, he held firm to his coaching philosophy, which had brought him significant success back in Portugal.

An insider revealed: "Amorim made it clear when he spoke to United about becoming the coach that he needed the freedom to play the way he did in Portugal."

"Sporting, like United, have a reputation for developing their own talent and their academy also traditionally used 4-3-3. But when Amorim became the coach there was also a shift towards 3-4-3 and 3-4-2-1 at youth level to mirror the first team.

"If you look at how Sporting played in the UEFA Youth League this season, you will see that they played with all three formations."

When Amorim took charge of Sporting, he decided on some hard-hitting changes, reminiscent of challenges he met at Old Trafford. He ruthlessly abandoned the 4-2-3-1 stance inherited from Silas, immediately implementing his own game plan.

In pursuit of dedication to his methods, supporter-loved players such as Marcos Acuna and Islam Slimani were offloaded from Sporting, a decisive move hinting that stalwarts like Marcus Rashford and Alejandro Garnacho may similarly be on borrowed time if they can't conform to Amorim's rigorous standards at United.

Sporting CP revolutionised their recruitment strategy, bringing in talents such as Pedro Goncalves, Pedro Porro, Joao Mario, Nuno Santos, Zouhair Feddal, and Bruno Tabata to fit their tactical blueprint. The promotion of youth prospects Matheus Nunes, Eduardo Quaresma, Nuno Mendes, Joelson Fernandes, and Tiago Tomas resulted in Sporting clinching the Portuguese title after a 19-year drought, losing only once that season.

Under Amorim's guidance, they lifted the trophy again the following year and have continued their success this season, despite a brief tenure from Joao Pereira and Rui Borges's change to a 4-4-2 formation. Following Amorim's move to Manchester, he left Sporting dominating with an average of 65 percent possession in league matches.

Now at United, he has frequently spoken about the support he requires from the club's hierarchy. A source revealed: "Of course Amorim would like money to use in the transfer market. But he also needs to be given the freedom to impose the methods he believes in on the club."