Arsenal have already signed their Kieran Tierney replacement, as Mikel Arteta plots the next phase of his tactical evolution

Arsenal full-back Kieran Tierney has struggled for minutes since the emergence of Oleksandr Zinchenko at the Emirates Stadium. With Mikel Arteta still not starting the Scot in two dead rubbers at the end of the season though, one thing's become clear: he's surplus to requirements. 

Tierney is expected leave after four years in north London, with Aston Villa and Newcastle both interested. It's a perplexing turn of events, given that the left-back has been one of Arteta's most trusted players over the years – first in a back three before establishing himself as one of the best full-backs in the league.

But with Arteta looking to evolve his side, his new Tierney won't be a direct replacement – in fact, Arsenal aren't linked with any left-backs in the transfer market. That's because the replacement could well have already been made…

Arsenal have used an inverted full-back instead of Kieran Tierney side of the pitch in recent months

Let's go back to some basics, here. In a game against Watford towards the end of the 2021/22, Granit Xhaka began marauding forward, with Kieran Tierney inverting at full-back. That was a sign of things to come. 

Oleksandr Zinchenko joined in the summer – and Tierney struggled to earn his place back. Above, you can see how the Gunners use Zinchenko to create a famed 'box midfield' ahead of a back three in possession: while Tierney is more of a traditional overlapper. Against Liverpool, Arteta cited picking Takehiro Tomiyasu over Tierney as "tactical" and during a friendly scheduled over the World Cup against Juventus, the Scot was again seen drifting into midfield, attempting to play 'the Zinchenko role'.

Tierney just didn't feature regularly in the second half of the season, though. When an injury to Zinchenko came against Newcastle, the No.3 was dropped into the action – but against Nottingham Forest and Wolves in what were essentially dead rubbers, Arteta opted for something new. 

Mikel Arteta may now look to replicate the same dynamics on the other side of the pitch… making Jakub Kiwior the new backup left-back

Instead of bringing in Tierney for those last two games of the season, Arteta chose Jakub Kiwior: a left-footed centre-back who can play at left-back and in midfield.

It seems as if Kiwior is the replacement for Tierney: a competent left-back who can fill in at centre-back if needed. It makes sense, too: Arsenal have used Ben White as a natural centre-back at right-back, just as Manchester City have done the same. The Gunners wanted Lisandro Martinez for the same role on the left last summer but ended up signing Zinchenko.

Against Forest and Wolves, too, the inverted dynamic shifted to the other side of the pitch with Thomas Partey. Arsenal are said to be interested in Moises Caicedo – who can play at right-back – but haven't been linked with a new left-back, with Tierney all but certain to exit.

As Arteta continues to evolve this side, it perhaps isn't a surprise that the replacement for a natural left-back is actually a natural centre-back: just look at City. With Granit Xhaka likely to leave, too, opportunities will be presented to Fabio Vieira and Emile Smith Rowe – two attacking midfielders who lack physicality – and that requires something a little different behind them.

Inverted full-backs are clearly en vogue. It's possible, too, that Kiwior and Tomiyasu play either side with a John Stones-like libero in the centre of defence… Ben White, maybe?