When Pep Guardiola allowed Joao Cancelo to move to Bayern Munich in January without signing a replacement, it led to some head-scratching. This was Manchester City’s right-footed inverted left-back. There was no one else in the squad capable of performing such a unique role in such a structured system.

What would City do? Guardiola must have let out a chuckle around then as he sat admiring his ink-still-wet blueprint for City 7.0.

In the weeks since, he has simply reinvented Nathan Ake as an impregnable left-back and created a new shape in which 28-year-old John Stones has hatched as a defensive midfielder/centre-back/right-back hybrid. Simple.

Kyle Walker was the casualty of the new shape for a month before it was slipped back up Guardiola’s sleeve at the weekend in favour of blowing the dust off an old favourite against Leicester City. Different horses for different courses — knowing the limitations of each player and when the mix of skill sets available requires a tweak or two.

This is also a luxury for City that has been years in the making.

As they shape-shift in pursuit of a fifth title in seven seasons under Guardiola, though, the wheels of league leaders Arsenal’s own well-oiled machine look to be wobbling slightly as they realise just how indispensable every cog is to their established way of playing.

Missing injured centre-back William Saliba, and the subsequent drop-off in quality that comes with playing replacement Rob Holding, was one thing. But also having Oleksandr Zinchenko out for last weekend’s game at West Ham meant half of the first-choice back four were absent for the first time all season – one of them the player whose inverted role is so important to providing Arsenal with the fluidity and control they desire.

There were no surprises that Mikel Arteta chose to replace Zinchenko with Kieran Tierney, who was making his first league start since December, but he was also asked to try to replicate the Ukrainian’s inside role rather than play as a conventional full-back.

There was a five-minute spell in the first half when Tierney made two trademark bursts down the left flank, while a second-half delivery flashed across the face of goal that really ought to have been turned home. That was the Scot at his natural best but those moments were fleeting.

Tierney was usually standing somewhere to the left of Thomas Partey in central midfield, looking slightly too hyper-aware of his surroundings for it to be natural. He was tidy enough on the ball but there was still an air of hesitancy where you could see his brain was trying to compute what still must feel like an alien situation for him, given his lack of game time in recent months.

When he performs that role while deputising for Zinchenko, there are not the same cute combinations and disguised passes through gaps to break the opposition press.

Tierney has shown at international level that he is positionally versatile, having played centrally in a Scotland back four but more regularly been deployed by his country on the left of a back three, from where he drives forward with the ball.

Surely, for one game, Tierney, a player who would walk into most other Premier League sides, could hold the width and overlap so Arsenal can use his acceleration in attack? Asking him to fit into such a tactical straitjacket contrast with what Guardiola said earlier this month about his decision to omit Walker from his new three at the back, two in midfield build-up shape.

“To play inside you have to have educated movements. He (Walker) doesn’t have every one of the characteristics,” Guardiola said. “He has played as a full-back coming inside in the past with four at the back. He has done really well but this shape of three at the back and two in the middle, he cannot do it.”

Down in north London, having built possession like this on Arsenal’s left side all season, Arteta clearly believes the continuity of the system, and opening up those same rotations between Granit Xhaka and Gabriel Martinelli, trumps individual preference.

A pragmatic change to their build-up play may have quelled the issues Arsenal faced in possession as the West Ham game went on, but who can blame Arteta for prioritising familiarity given the degree to which his team have overshot where they were predicted to be this season?

It has taken more than three years for him to get Arsenal to perform with this level of coherency.

He had to jump from one formation to the next in his first two full seasons due to the overturn in players. Now he has built a team capable of being Premier League front-runners for so long, Arteta isn’t at the place where he is prepared to start mixing it up down the home stretch of a title race.

There is a core of 13 or 14 players and he deviates as little as he can from the personnel and style they have worked religiously towards. Changing Tierney’s starting position would mean changing things that had become automatic for Gabriel, Xhaka, Martinelli and Partey.

Arteta opting to use the Scot inverted was not the reason Arsenal let their two-goal lead slip at the London Stadium but it was telling that, even with two key players out and their possession game affected, he chose to stick rather than twist.

To be able to change in-game and ask players to switch between one role and another requires an unerring level of faith in their abilities, both technically and tactically. While it could be perceived as him backing Holding and Tierney to fit in seamlessly, it appears Arteta is not yet at those trust levels with enough of his squad to be comfortable asking them to play different tunes.

Again, Arsenal have only this season nailed down this way of playing with this group of players. They have, in their manager’s eyes, only just moved into phase three of five in his long-term plan. That means the club’s squad-building is unfinished, leaving the manager with fewer options than Guardiola.

Arteta has swapped parts along the way and he will continue to do so in the summer when Arsenal are likely to reinforce their midfield and back line.

That will, you’d hope, reduce the gap in quality between the first- and second-choice players in certain positions but, more than that, will provide him with the versatility to be able to change when injuries hit or the opponents nullify an aspect of their play – as well as compete on multiple fronts now that a return to the Champions League is all but guaranteed.

There have been signs of Arteta’s desire to reach the point where his team can morph mid-game. Ben White and Takehiro Tomiyasu have swapped in and out to offer different profiles, sometimes with the latter even playing left-back, while January signing Leandro Trossard and Martinelli have dovetailed between the left wing and striker positions in the last two months to make it hard to tie them down.

City have Rodri, but they also have Bernardo Silva and Ilkay Gundogan capable of providing control. Kevin De Bruyne and Phil Foden have both been used deeper at times and now Stones can also do it in another way. That is the level of squad strength Arsenal require to assert the control they desire for full matches throughout a season, but it will take them time to get there.

For now, Arteta dare not risk straying from the formula that has got them so close to their first title in 19 years.

• The Athletic report / By Jordan Campbell