When Luke Shaw plays 30 games in a season for Manchester United, they win. When he doesn’t, they lose.

There is a direct correlation between the England full-backs fitness and the performance of the team as a whole.

Between 2019 and 2021 under Ole Gunnar Solskjaer, Shaw was promoted to lead the left side of United’s defence. He played in 56 of Solskjaer’s 76 games in charge during that time – a record over two seasons he hasn’t beaten since.

It’s no coincidence that United played their best football since Ferguson retired during this period, finishing 3rd and then 2nd – their best attempt at a title challenge in a decade.

Shaw’s form was impressive too. He finished with 5 assists and 3 assists in those seasons, providing valuable contributions overlapping Marcus Rashford on the left of United’s attack. His pace and composure were perfect for well-timed bursts as United played a well-rehearsed brand of counter-attacking football.

This helped Shaw. United often surrendered the ball, meaning Shaw was able to sit back, often getting help from his winger on the left side, before driving forward when United recovered the ball. His adventures into the opposing half were sporadic, well-timed and often effective.

In the current Amorim system, the wing-backs are required to do a lot of running, hold the width and spend a lot of time on the touch line. This doesn’t suit Shaw, so even when he returns, I wouldn’t expect him to be the answer to United’s wing-back problem.

His form in 2020-21 resulted in a recall to the England squad and a starting spot at the Euros as England made it to the final, which he scored in. When he returned to United after the tournament, he suffered further injury setbacks, no doubt caused by the increased playing time and the stress this would naturally cause a player with 3 metal pins in his leg.

Returning in the 2022-23 season under new manager Ten-Hag, Shaw was excellent, helping United to a top 4 finish. But, there was no doubt he was less effective and had it not been for Malacia’s excellent debut season, United would have struggled to cover for Shaw as he regained his focus.

And here is where we can look closer at United’s left back issue more generally, using Malacia as a good case-in-point.

When United play a naturally left-footed full-back, they tend to do much better than when they don’t.

Diogo Dalot and Aaron Wan-Bissaka played the majority of games last season at left back when United finished 8th – their lowest finish in the Premier League era. Neither are naturally left footed.

This season, Diogo Dalot has again been doing his best to fill in at left wing-back. He’s industrious, he tries hard and he is solid defensively. But going forward he offers little-to-no threat, as emphasised by his poultry one assist this season.

United find themselves 12th in the league at the time of writing, having won 2 of their last 10.

In the two games Shaw has managed to take the field this season (both were from the bench) United have avoided defeat, even beating Everton 4-0 in the second appearance.