The signing of Carlos Baleba completes a £155m summer revamp of Manchester United’s midfield.

At the end of last season, midfield was targeted as a priority area as United looked to build on qualification for the Champions League after a two-year absence.

Baleba arrives along with Andrey Santos, a £48m signing from Chelsea, and £35m former Aston Villa man Youri Tielemans.

It means that, along with England’s Kobbie Mainoo, United now have a spread of different attributes across their four-man midfield, three of whom are 22 or younger.

But, at Manchester United, one bad result brings intense pressure.

Even Michael Carrick’s calm exterior cracked in a post-match exchange with former Middlesbrough and Swindon Town forward Jan Aage Fjortoft, now a TV presenter for Viaplay, following the shock defeat at Hull when the Norwegian suggested there was a lack of passion in United’s ranks.

“Come on, that’s ridiculous,” replied Carrick. “You played football. You understand. That’s a ridiculous thing to say.”

So, now the midfield is sorted, it is natural for fans to look at the other areas of Carrick’s squad that could do with reinforcements; namely left-back.

Signing an additional left-back has looked an obvious thing for Manchester United to do.

Luke Shaw started all 38 Premier League games last season. He started at Hull. Of United’s past 44 league games, the 31-year-old England international has failed to start just one, the final game of the 2024-25 campaign, four days after the Europa League final defeat by Tottenham – and he went on the post-season tour of Asia immediately afterwards.

But, before that, Shaw’s injury record had not been great.

Between February 2024 and April 2025, he played as many games for England (three) as he did for his club. He missed three months at the start of the 2023-24 campaign.

There were calf and hamstring issues but also a feeling Erik ten Hag rushed him back too quickly.

More than anyone, Shaw benefited from a 40-game season, allowing him to prepare properly, largely for one game a week, sometimes not even that.

That preparation time will not be repeated.

Although there are blank midweeks between Manchester United’s first three games, if they get through two EFL Cup rounds, they will not have a full midweek without a game, other than during international breaks, until the one that includes Christmas Day.

It is the combination of Shaw’s injury record and the crush of games that has led to the feeling another left-back will arrive.

There is no doubt the club like Newcastle’s Lewis Hall. At 21, he is the right age profile and ideally suited to challenging Shaw for his place, with the safety net of there being enough games to keep both men happy.

However, Newcastle don’t want to sell. It would take a huge offer to persuade them otherwise and Manchester United’s powerbrokers have proved on numerous occasions this summer they will not be held to ransom, or overpay, for players.

In addition, how much money do they have to spend?

In published third-quarter financial accounts to 31 March, United confirmed they owed £405.75m in outstanding transfer fees, £171.14m of which was due after more than one year. The club are still to outline what the additional $125m (£91.64m) they borrowed in a wider refinancing announced in June will be used for.

The assumption is £70m for Baleba, equal the sum United paid for Casemiro in 2022 and a figure only exceeded in their history in terms of midfielders by the club record £89m spent on Paul Pogba, is at the top end of what they wanted to pay.

Plenty of alternative left-backs to Hall have been mentioned.

Racing Santander’s 19-year-old Jorge Salinas has a €16m (£13.7m) release clause, but is also coveted by Atletico Madrid.

Barcelona’s Alejandro Balde was left out of the 5-0 La Liga victory over Elche by coach Hansi Flick, to allow him to “clear his mind” amid intense transfer speculation, with United among those to be linked with the 22-year-old Spain international. Barcelona are said to value him between €30m (£25.66m) and €40m (£34.22m).

With a week to go before the transfer window closes, the situation is thought to be fluid, but caution in United circles around the expectations of a new left-back being signed is being stressed.

A significant sale could change the dynamic.

However, the idea of Marcus Rashford leaving has virtually been ruled out with confirmation he will wear the coveted number nine shirt this season, while the anticipated exit of Manuel Ugarte had to be scrapped when he was injured at the World Cup.

Of Carrick’s senior squad, forward Joshua Zirkzee appears surplus to requirements, yet with fitness doubts over Amad Diallo – the club are choosing to offer no clarification on the extent of his injury amid a report he could be out for up to six weeks – it is uncertain whether interest from Serie A will lead to a sale.

Carrick does have options at left-back without bringing anyone else in. Diogo Dalot and Noussair Mazraoui have both switched flanks in the past, while Baleba, a left-footed player, has played at full-back for Brighton previously.

In addition, Harry Amass was Shaw’s back-up during pre-season and the 19-year-old remains at United. But he was not included in Carrick’s squad for the Hull trip and the expectation has been he will leave, either permanently or on loan.

Most still think there will be another left-back in Carrick’s squad when the transfer window closes on 1 September – but it is by no means certain.