Having lost four games on the bounce, Manchester United would be within their rights to attack this month's transfer window in an effort to drag themselves out of trouble.

However, the word from the club is that there is "no money" to spend on prospective recruits this month. United spent north of £200million in the summer but recruited to the needs of their former manager and a different formation.

Following the appointment of Ruben Amorim in November, United now operate with a 3-4-3 system. The Portuguese head coach was wedded to that shape at Sporting Lisbon and wasted no time in implementing an identical shape at Old Trafford.

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The three-at-the-back system features wing-backs that provide the width, both defensively and offensively. They are arguably the most crucial components within the formation.

Amad, in the main, has been United's first-choice right wing-back since Amorim succeeded Erik ten Hag, offering plenty of promise and productivity from that position. In recent weeks, however, he has been tasked with playing higher up the pitch as the right-sided No.10.

As a result of that switch, Noussair Mazraoui has generally operated as the right-sided wing-back. Diogo Dalot has regularly operated on the opposite flank despite being more comfortable on the right flank.

As a result, is it felt that signing a left-sided wing-back should be a leading priority for United before the end of the January transfer window in the event of funds becoming available. United know they need to cut their cloth to raise funds for potential incomings and Amorim, speaking at Friday's press conference, admitted the club will "try to do something" before the deadline on February 3.

He said: "Of course, when the window is open we can try to do something and we will try to do something, but in the next weeks we are going to have more time to train and we have to improve. That's the only way because we had a lot of games without training."

Signing a left wing-back is considered as a necessity by United supporters and journalists alike, and a flurry of names have been linked with the possibility of filling that void at Old Trafford in recent weeks, including Paris Saint-Germain's Nuno Mendes. The Portuguese international is out-of-contract in the French capital in June 2026 and he is reportedly against signing a new deal.

He has struggled for regular game time this season, making just 16 appearances all competitions. He joined PSG in August 2021 from Sporting Lisbon, initially on loan, having caught the eye in Portugal under Amorim.

Mendes, 22, made 47 appearances for Sporting, all of which were made under Amorim's watch. He regularly operated as the left wing-back, regularly getting forward and supporting the attacks with his blistering pace.

Like so many others who have come through the Sporting youth system, Mendes was prized away. Amorim, understandably, was sad to see him go.

"It's a shame to see him in a PSG shirt," Amorim said. "I wish him all the luck in the world. He's missed because he was a really funny kid."

When Mendes was pushing for his Sporting debut in 2020, Amorim paid the wing-back the ultimate compliment, insisting he was ready to become a starter already, explaining: "It doesn't mean he's going to play, but Nuno Mendes is ready to be a starter. There are a lot of quality players, we have a lot of them and there isn’t room for everyone right now.

"We have a very large group and there are others that I would like to call up if the squad wasn't so large."

Having held Mendes in such high regard five years ago, Amorim is unlikely to have any concerns about using him as a starter at Old Trafford should a deal be done this month.

His current situation at PSG makes a move for the 22-year-old somewhat plausible. However, exits will ultimately decide if a deal is possible or not.