When Trent Alexander-Arnold and Andrew Robertson put up 48 assists between themselves in the two
Premier League seasons between 2018 and 2020, you might have been forgiven for
thinking the end point had been reached in the evolution of the modern full back.
With Klopp’s midfield prioritising intensity and pressing, the German had looked elsewhere
for his creative output and settled upon his full backs, both of whom would push
forward into the attacking line to help Liverpool generate chances, albeit in very different ways.
At that point, it seemed like high energy, attacking full backs were here to stay. But
in the short time that has followed since Liverpool’s Premier League title win,
the role of the full back in the modern game has continued to evolve to the extent that
Brazil could field full backs who barely made it across the half way line in 2022.
So what has happened to the full back position in modern football?
There are no new ideas in football. Just new contexts in which old ideas seem revitalised.
This is certainly true of the full back position. At various points of football history,
you could find full backs overlapping; full backs underlapping; and full backs inverting.
What has changed for the full back role in recent
seasons is the context within which the position is understood tactically.
Jurgen Klopp’s Liverpool is a good example of how the context impacts the position. For
a few seasons, flying full backs proved to be their triumph, carrying them to Premier
League and Champions League titles. But very quickly, oppositions have learned to exploit
the weaknesses that pushing your full backs high introduced into Liverpool’s structure.
The outset of the 22/23 season saw oppositions targeting the space left open behind Liverpool’s
full backs - particularly Andy Robertson - pulling the backline across and then overloading the space
around the opposite full back. Questions have been raised about Trent Alexander-Arnold’s
defending but much of the issue has come from the aggressive way Liverpool use their full backs. As
the context has changed, so the role of the full back has had to change to reflect it.
Rather than committing full backs forward, then,
some managers have preferred to keep them deeper. For example,
in the last couple of seasons, we have seen a resurgence of managers using inverted full backs.
The principle of inverting full backs is quite simple. In certain phases of play,
the full back will move inside the field in a much
more narrower configuration than you might expect from a full back.
This has a number of benefits for a team. In possession, it keeps the deeper players in a
team closer together which can help them possess the ball between themselves more comfortably.
It also allows the team in possession to “pin” the opposition midfield into a
more narrow configuration. With the full back moving inside, the opposing wide player who is
closest to them may track them inside, leaving space that can be exploited during build up.
Out of possession, the inverted full back gives an upside which can help mitigate
the effects of using advanced full backs in possession. By moving a full back inside,
a team can construct a solid defensive base from which they can defend in transition.
By overloading the middle, the team defending the transition does leave a lot of space that can be
exploited in wide areas. However, the logic is that the ball and the opposition players have to
travel a longer distance than the defending team in order to cause them any problems.
And importantly, there is an additional benefit here. With one or both full backs inverted,
the distance that the full back has to travel in defensive transition is
much less than the distance that an overlapping full back has to travel.
But it’s important to remember that this more conservative approach to full backs comes at a
cost. Where the inverted full backs of more recent popularity will give you a more stable defence,
the flying full backs of Jurgen Klopp’s Premier League winning team offered Liverpool a huge
amount of creative upside which offset the space they left open in their wake.
The question is: can you get the best of both worlds? Defensive solidity and
attacking upside? And this brings us to Diogo Dalot.
Since arriving at Manchester United, Erik ten Hag has implemented a system in which the full
backs invert in certain situations. Diogo Dalot is perfect for this kind of role. A
good technical player, he can move inside and help with central build up with the
added benefit of covering the centre in the event of a turnover of possession.
But with the ball moving into the final third, Dalot is given a freer role. If the
right winger has come inside, he can move into the wide channel and function as an
overlapping full back. If the right winger is hugging the touchline, then he can underlap.
But perhaps most commonly, you’ll find him operating on the edge of the box,
ready to engage in build up or spring a counterpress against the ball.
Where the role of the full back was thought of as fairly basic—perhaps unfairly —the modern
full back is expected to fulfil a number of roles both in and out of possession.
In Diogo Dalot, Manchester United have a player who can contribute to build up,
can help out in attacking phases but who is also an important cog in their defensive structure.