One of the easiest and most misleading pieces of footballing received wisdom is that everything is cyclical. Wait long enough, the great drum of history will revolve again and the same ideas will come back round, be that sharp side-partings, the back three, Howard Webb apologising to Brighton or Roy Hodgson managing Crystal Palace. Except time is not a flat circle. Each iteration is different because it comes with knowledge of what went before. Watch Manchester City in possession. They have a centre-forward and two wide men. They have Kevin De Bruyne and Bernardo Silva or Ilkay Gündogan as “free 8s”, essentially old-fashioned inside-forwards. They like to have five outfielders behind the ball, who will usually form a trapezoid shape: a line of three defenders and two deep-lying midfielders. Show that to Herbert Chapman and, while he may think City could be a little more direct, he would understand what he was seeing. This is essentially a W-M. But this is not Pep Guardiola simply appropriating a formation from almost a century ago. A lot has happened since, not least the coming of zonal marking, so the game is no longer the series of individual battles it was in Chapman’s day. Indeed, it’s entirely likely Guardiola is yet to form strong opinions on Arsenal’s title-winners of 1930-31 (although you suspect that in the key dispute of the age he would go against Chapman and favour the ball-playing qualities of Jack Butler at centre-half over the gangling stopper Herbie Roberts). Rather it’s that the trapezoid shape has proved over time extremely effective at preventing counterattacks. That’s why the 3-4-2-1 had its brief vogue, most notably as Chelsea won the league under Antonio Conte in 2016-17. But the problem with that shape, as has subsequently been seen at Chelsea and Tottenham, is that while it may be solid, it is very dependent on the wing-backs to provide width and on the individual inspiration of the two creators playing off the striker. It can become predictable. If you want to be flexible, then, how can you create that three-two anti-counter trapezium? Often teams playing a back four would allow both full-backs to advance, with a holding midfielder dropping in between the centre-backs to create the line of three. Or one full-back would go forward with the other tucking in alongside the two central defenders. That was how it worked for Guardiola at Barcelona, when Dani Alves would habitually charge forward supporting David Villa on the outside, with Sergio Busquets slipping between the central defenders or Eric Abidal shuffling across. At Bayern, though, blessed with a player as tactically accomplished as Philipp Lahm, Guardiola began experimenting with having one of the full-backs advancing into a deep-lying midfield role, rather than providing attacking width. At City, Guardiola has sometimes had two attacking full-backs who would overlap – Bacary Sagna or Jesús Navas and Gaël Clichy or Aleksandar Kolarov in his first season, for instance – but he has also tried the Lahm protocol, occasionally with Fabian Delph, most successfully with João Cancelo, most implausibly with Bernardo Silva, and most recently with John Stones – even if, in Tuesday’s win against Bayern Munich, Stones was stepping up from a central position, with Manuel Akanji and Nathan Aké almost as old-school, orthodox defensive full-backs; it may be that the solidity of Aké is one of the factors in Jack Grealish’s run of form, that he no longer has Cancelo inside him, impinging on the space he would naturally like to attack. For three decades full-backs have been at the forefront of tactical development. As they have become increasingly attacking, so wingers have increasingly cut infield, which in turn made possible the rise of the false 9. Guardiola, so far, is unusual in his use of the full-back as an auxiliary wing-half, but it may be that this is the logical next step in the general development of the full-back. There is, perhaps, a gradual turn against the modish idea that full-back is an essentially attacking position. For full-backs to operate as high as, say, Trent Alexander-Arnold and Andy Robertson have for Liverpool, demands the press be all but perfect. If it is not, as in 2020-21 and again this season, opponents can exploit the space behind the full-back. When Mauricio Pochettino was at Tottenham, he in effect had four wing-backs on rotation because of the physical demands on them covering the length of the pitch; having them shuffle into midfield at least part of the time may be a way of mitigating the strain. There has long been an argument that Alexander-Arnold would be better deployed as a midfielder rather than as a right-back, initially on the slightly spurious grounds that it would involve him in the game more (a line of thought that seems to underestimate just how important the full-back position is in modern football), and more recently because, as Liverpool’s press has faltered, Alexander-Arnold’s defensive shortcomings have been exposed. How plausible the idea of Alexander-Arnold as a hybrid full-back/wing-half is remains debatable. Appealing as the prospect of him dictating the play from deep may be, it would if anything place more demands on the defensive side of his game, while reducing his crossing opportunities and limiting his interactions with Mohamed Salah, which were such a key part of Liverpool’s play last season, his overlaps encouraging Salah’s darts infield. But then if Liverpool’s press improves again, those defensive issues may recede and it’s just about possible to imagine a future in which Alexander-Arnold can be both an overlapping full-back and a full-back/wing-half. Given that Jordan Henderson will be 33 in June, it may be too late, but the Liverpool captain, a very good crosser of the ball, would seem to have the ideal game to interlock with an Alexander-Arnold who sometimes bombs on and sometimes tucks in. The issue, though, goes beyond specifics. For 60 years full-backs have been become increasingly attacking, to the point that almost every full-back is in effect a wing-back. The question was always what came next: how would full-backs evolve when there was no more attacking to be done. This, perhaps, is the answer: by helping to recreate a shape in possession that is itself almost a century old. The spiral of history revolves again.