Luke Shaw is the only specialist left-back in Manchester United's squad.
Bar right-wing, it is in fact the only position where United are unarguably under-stocked and so Shaw's absence from tonight's mammoth Champions League tie against Barcelona will be harshly felt.
That's despite the fact the 23-year-old suffered a night to forget in the first leg at Old Trafford , picking up a booking for a cynical tug on Lionel Messi's shirt and putting the ball into his own net to gift the Catalans a 1-0 aggregate lead.
But it still begs the question how United will fare without one of their more consistent mainstays this season. Few have been as pivotal as the left-back this term, so as he watches on from the Nou Camp stands, having travelled with the Red Devils' squad, what tends to happen when Shaw isn't on the pitch?
The record
United have played 37 games with Shaw in the side this season, winning 21, drawing six and losing 10 — a win percentage of 57 per cent. However, every game Ole Gunnar Solskjaer has lost since replacing Jose Mourinho has come with Shaw in the side.
Their record without Shaw is slightly worse in 2018/19, winning five, drawing three and losing two.
Yet the only games Shaw has missed under Solskjaer have all been victories: the 2-0 FA Cup win over Reading, 2-1 league wins over Brighton and West Ham, although United's record without Shaw under Jose Mourinho was less than impressive.
Shaw wasn't a part of the United sides that lost back-to-back games to Valencia and Liverpool in December, which eventually cost the Portuguese his job.
Last season, the difference in United's form with and without Shaw was even more stark.
The former Southampton star was out injured from the start of the season until December 5th, after which United's form picked up and they won 10 from 14 games with him in the side (a win percentage of 71 per cent).
The solution
Ashley Young was the more regular choice at left-back under Mourinho last season and could return to that position in the Nou Camp tonight.
But what alternatives do United have?
There has been some talk that Diogo Dalot could slot into the left side of defence, despite having largely been used further up the pitch by Solskjaer — occasionally in the front three. The youngster may be seen as a risk, especially given that he'll be going up against Lionel Messi.
Marcos Rojo returned from the wilderness against West Ham United but looked as rusty as a player who'd played 13 minutes of football in 2019. You cannot really imagine the United coaching staff throwing the Argentine into a battle against his fellow countryman Messi on the back of such a run.
If it is Young, United will know what they're getting: an experienced and vocal member of the squad who has transformed himself from the most inconsistent winger in the league, to a very dependable performer.
The issue for United may come when Young is asked to overlap — and let's not forget United will have to attack to overturn that 1-0 deficit — he won't risk leaving his position if it means space for Messi and company. So the visitors may be left without a genuine wide left option, especially is Solskjaer's diamond formation continues as expected.
In short, Luke Shaw is arguably as big a miss as anyone in the United squad and the task at Barcelona tonight is most certainly tougher without him.
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