Ruben Amorim had not even stepped foot on English soil and conversations about what Manchester United could look in his trademark 3-4-3 formation were rife.

Amorim had enjoyed no shortage of success in Portugal with Sporting Lisbon operating with a three-at-the-back formation and his appointment generated a feeling of excitement among United's supporters, who immediately sensed that something fresh was in the offing.

United's football under Amorim's predecessor, Erik ten Hag, had become stale, meaning the anticipated switch from a 4-3-3 to a 3-4-3 was exciting.

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However, understandable concerns were aired when analysing the wing-back department. Without Luke Shaw and Tyrell Malacia at the juncture of Amorim's arrival, United's only available full-backs were Noussair Mazraoui and Diogo Dalot.

Mazraoui had been signed from Bayern Munich in the summer to replace Aaron Wan-Bissaka, who had moved to West Ham United, and compete with Dalot at right-back. However, Shaw's never-ending injury nightmare and the fact Malacia is not a wing-back has meant Mazraoui has had next to no competition with Dalot, with the latter regularly lining up as the left-sided wing-back.

Naturally a right-sided player, Dalot, who was restored to the starting XI against Brighton & Hove Albion on Sunday after missing the clash with Southampton three days earlier through suspension, has done well in the absence of a genuine competitor on the left, but it is clear that he is not a long-term solution in that role.

Amorim's three-at-the-back system revolves around the wing-backs, both offensively and defensively. Gary Neville said as much after United were beaten 2-0 by Newcastle United last month.

"I think if you were starting, you'd have to start with the fundamentals of this system, which is the wing-backs, they hold it together," Neville said.

"If you don't have the wing-backs functioning up and down that are able to attack and defend equally as good, and there aren't many of those around, by the way, because there aren't many teams that play wing-back, then you're going to struggle.

"So you need two quite unique players in those wide areas, and I think that will be the starting point."

Fundamental to Amorim's system and his way of playing, United desperately need to add fresh blood to their wing-back department, particularly on the left side, and that is why they are pursuing a move for Lecce's Patrick Dorgu.

The Manchester Evening News understands that United are in talks with the Italian club to try and bring him to Old Trafford ahead of the transfer deadline on February 3. United want to sign a left-sided player and Dorgu would give them the answer they are looking for in their quest to solve that particular mission.

The Denmark international, 20, has earned rave reviews from those who have watched him regularly in Italy. He is highly versatile, capable of playing on either the right or the left, and he has pace to burn, making him suitable for the wide roles in Amorim's system.

Dalot, through no fault of his own, has regularly had to play on the left because of injury issues elsewhere in the squad. United need a long-term replacement for Shaw and Dorgu is being targeted with that in mind.

The Copenhagen-born ace is best-in-class when it comes to wing-backs' attacking actions, making him an attractive fit. Furthermore, in the words of Lecce's sporting director, Pantaleo Corvino, he has an engine that is unrivalled.

Speaking to Gazzetta dello Sport last month, Corvino said: "Dorgu is a potential champion. Correction: he is a champion.

"Left or right winger, he runs like three players and can find the goal. He has an engine that no one else has. A player like him has admirers, of course, and there are plenty of them, even abroad."

Dorgu is familiar with operating as a wing-back, meaning United would be inheriting a player suited to Amorim's system. It has been clear to everyone that United must strengthen that area of the team with a natural wing-back operator, and not a full-back that needs time to adapt to a new role.

Despite not turning 21 until October, Dorgu is already experienced enough to understand what Amorim will demand of him. He ticks a variety of boxes and his ceiling his very high.

It has been blindingly obvious ever since Amorim walked through the door that signing a left-sided wing-back had to be a priority in January. It now looks as though United might be attempting to land one of the most exciting options possible.