Man Utd have no-brainer open goal to upgrade squad in January after £5m transfer blunder

Manchester United are closely monitoring Alvaro Carreras’ development after allowing him to join Benfica permanently for just £5million in the summer, according to reports. That decision has proven controversial, and not just because the 21-year-old defender is mightily impressing in Portugal.

United allowed Carreras to end his loan at Granada to join Benfica in January, initially on a temporary basis before the permanent deal.

The Spain U21 international’s potential was never in doubt as he rose through the youth ranks at Carrington, but no first-team opportunities emerged.

Erik ten Hag’s decision to loan Carreras out while left-back has been one of his primary problem positions at Old Trafford has raised eyebrows.

Last season, Tyrell Malacia’s pre-season injury and Luke Shaw’s absence prompted United to recruit Sergio Reguilon on a short loan.

But Carreras was right there, and rather than recalling him from Granada in the winter, he was shipped off to Benfica instead.

After sending Reguilon back to Tottenham in the same month, a reoccurring injury to Shaw left Ten Hag with no natural left-back for the majority of the dismal campaign.

United didn’t learn their lesson in the summer. They trusted Shaw and Malacia to provide two left-back options again, but neither has featured in the opening 11 matches as they recover from their respective issues.

Diogo Dalot has covered on the left of Ten Hag’s defence this term, with Noussair Mazraoui heavily featuring at right-back after his £17m switch from Bayern Munich.

But Mazraoui’s upcoming short-term absence after undergoing a minor procedure, having experienced heart palpitations, leaves Ten Hag’s options bare.

The Dutchman may not survive the sack to see the January transfer window, but whoever is at the helm must consider triggering the buy-back clause in Carreras’ Benfica contract.

While United have struggled in the position, he is going from strength to strength.

Carreras has established himself as Bruno Lage’s first-choice left-back, featuring in all seven Liga Portugal matches and starting the last five.

He has also played a full game in each of Benfica’s opening two Champions League fixtures – a 2-1 win against Red Star Belgrade and a 4-0 demolition of Atletico Madrid.

O Jogo report that Barcelona and Real Madrid join United in actively following Carreras’ progress. Atletico and Juventus have also been touted as suitors.

But the Red Devils will be first in line to secure his signature, and while the buy-back fee they agreed with Benfica is unknown, they must ensure they take the opportunity to fend off the competition.