Ezri Konsa's first Premier League start for Arsenal comes, by the fixture list's odd sense of humour, against Aston Villa — the club he joined from Brentford in July 2019 and left, six years and 286 appearances later, as one of the Europa League winners in that Villa dressing room last May. He walks out having missed the Coventry opener by design, William Saliba's understudy before he has kicked a ball, and the shorthand everywhere this week has been the obvious one: cover. Stopgap. A body for the six or eight weeks Saliba needs.

The shorthand is fair as far as it goes. It just arrived before anyone had watched the player do the job, which is how most transfer-window shorthand gets written.

The case against the signing deserves stating properly rather than waved past. Arsenal conceded 27 league goals last season, eight fewer than anyone else in the division, and won the title on the back of a four-game clean sheet run through April and May that Arteta's players will tell you, if you ask, is the actual foundation of everything that followed. Gabriel and Saliba, when fit together, are as settled a partnership as the club has had since Koscielny and Mertesacker. Spending £51 million plus add-ons on a third or fourth centre-back, when the goalkeeper and the two first-choice defenders were already the best-defended team in the country, looks on paper like money that could have gone to a midfielder who might have won you a game Arsenal drew. That argument was made loudly in August, and it wasn't a stupid argument. It's the argument you'd make about most squads that had just won the league conceding fewer than a goal a game.

What it misses is what Berta actually said when the deal was announced, which people read and then filed under standard-issue transfer quote rather than as a description of intent. "Being comfortable in both central defence and at right-back, Ezri will bring valuable versatility to our squad." Versatility is the word every sporting director uses about every squad player, so it's easy to skim past.

Look instead at what Konsa's numbers say he does, and the word stops being filler. He completed 95.5% of his passes in the Premier League last season, the highest figure among anyone who played over 100 minutes — and 93.8% of the passes he attempted under pressure, also a league high. He made 151 attacking line-breaking passes, more than any Arsenal defender managed. His duel success rate, 67.1%, was higher than Gabriel's, higher than Saliba's, higher than anyone currently on Arsenal's books. None of that is the profile of a squad-filler brought in to keep the seat warm for two months and hand the shirt back. It's the profile of a centre-back who spent six years also learning to play right-back.

Because the actual problem Arsenal solved last season wasn't shortage of quality. It was shortage of shape. Arteta's back four has needed, at various points, a right-back who can tuck into a back three, and cover for Timber and White that doesn't require reinventing the system every time somebody picks up a knock. Calafiori and Hincapie can do versions of this. Konsa arrives already fluent in it — 34 league starts last season, every one of them, plus every England game at a World Cup semi-final run. He is not depth in the old sense, a like-for-like replacement waiting in a drawer. He is a second grammar for the same defensive sentence.

None of which requires pretending the on-pitch numbers translate perfectly. He didn't score in 34 league appearances last season and managed eleven shots, and at defensive corners for Villa he won the first contact just three times all campaign — Martínez and Onana did most of that clearing work instead. If Arsenal need him at the near post in October, that part of his file is thinner than the rest.

What the last two Arsenal summers have taught anyone paying attention is that Arteta doesn't buy for the emergency he can see. He buys for the shape he wants to have available when the emergency he can't see arrives — a Saliba back injury in August, a Timber knee in September, whatever December decides to do to a squad playing four competitions.

Saliba will return, presumably to the shirt he's worn for three years, and the temptation in October will be to say the Konsa experiment served its purpose and can now be filed away.

The archive has a cleaner comparison than most people reach for. Kolo Touré arrived at Highbury in February 2002 as a versatile squad defender, signed for cover behind an ageing back line, and stayed as first-choice centre-back for the best part of a decade.

Nobody remembers the emergency he was bought for. They remember the player.