The window is open again. It's the third week of July, the market is doing its usual overheated thing on social media, and somewhere a bloke with a burner account is insisting a deal is "advancing" because a plane took off from Luton. None of that is the interesting question. The interesting one, six and a half years into Mikel Arteta's rebuild, is which windows actually changed the club's structure and which just changed its mood for a few weeks in August.

Most people rank transfer windows by fee, or by what the signings went on to win. That's a scoreboard, not an argument. Rank them instead by what each window forced the club to fix about itself — not just its eleven — and the order gets uncomfortable, because the biggest cheques don't come first.

6. Summer 2022 — Jesus and Zinchenko

Gabriel Jesus arrived from Manchester City for £45m, Oleksandr Zinchenko for £30m, and the effect was immediate and real: Arsenal went top of the table in August and stayed competitive all season. But this was a confidence window, not a structural one. Two players who already understood Pep Guardiola's positional logic, imported wholesale to teach it to a squad that hadn't yet earned it. It worked because the recipients were good learners, not because the club had solved anything about itself. When Jesus's knee gave out at the World Cup that November, the whole approach briefly looked borrowed rather than built.

5. Summer 2024 — Merino, Calafiori, Raya made permanent

Mikel Merino for £32.4m on deadline day, Riccardo Calafiori for £42m from Bologna, David Raya's loan converted for a reported £27m. This is the window that looks smallest on paper and reads best in hindsight — a goalscoring central midfielder and a left-footed centre-back who could carry the ball into the middle third, both filling specific tactical absences Arteta had been diagramming out loud in press conferences for two years. Competent, targeted, unglamorous. The kind of business that doesn't trend on deadline day and doesn't need to.

4. Summer 2025 — the most expensive window in the club's history

Martín Zubimendi, Viktor Gyökeres, Noni Madueke, Piero Hincapié, Cristhian Mosquera, Kepa Arrizabalaga made permanent. Six incomings, a reported outlay north of £200m, addressing the two absences Arsenal had pretended for three years they could paper over: a genuine goalscoring centre-forward and a defensive midfielder who reads danger before it arrives. This wasn't vision. It was correction, four windows overdue, and the fact that it took this long to admit Arsenal needed a striker is its own small scandal.

3. Summer 2021 — the reset after Villarreal

Ben White for £50m, Aaron Ramsdale for £24m, Martin Ødegaard made permanent for £30m after his loan, and a genuine cultural line drawn under the Özil era. This came five months after Arsenal lost the Europa League semi-final to Villarreal, 2-1 on aggregate, beaten by Unai Emery's old side in a tie that felt like the club being told exactly what it had become. What this window bought was standards — captaincy material, a goalkeeper who'd talk, a squad that got harder to embarrass. That matters more than any single name in it.

2. Summer 2023 — Rice, Havertz, Timber

Declan Rice for £105m, a British transfer record; Kai Havertz for £65m; Jurrien Timber for £38m, who tore his ACL on his competitive debut against Nottingham Forest before he'd played sixty minutes. This is the window most people would put first, and the case is strong. Rice alone ended two seasons of collapsing in games Arsenal were controlling on the ball but losing on the scoreboard. It's second here for one reason: it bought control of matches Arsenal had already learned, painfully, that they needed to control. It was the correct answer to a question the club had already asked itself.

1. January 2021 — the window that did nothing and changed everything

Arsenal sat fifteenth in the table that Christmas. The business that window amounted to almost nothing incoming and Joe Willock going out on loan to Newcastle, where he'd score eight goals in fourteen games and make the whole exercise look faintly ridiculous.

But the emptiness was the point. With no money and no alternative on the bench, Arteta had to keep starting Bukayo Saka, Emile Smith Rowe and Gabriel Martinelli — not as philosophy, as necessity — and an academy promise the club had been failing to keep for a decade got kept by accident, under duress, because there was nothing else in the cupboard.

Every window since has been an argument about how to spend money around three players the club discovered because, for one January, it had none to spend at all. Rank the windows by fee and the list flatters the men writing the cheques. Rank them by what they fixed, and the most important business Arsenal ever did was the summer they were too broke to do any.