If Arsenal do what, with each passing week, seems increasingly likely then this moment will resound through the years. The best title-winning campaigns all contain those flashes in time that set fate’s course: as Arsenal’s substitutes and coaching staff piled on to the pitch in delirium, the Emirates stands a blur of limbs and faces to an extent rarely seen, it was hard not to feel that Reiss Nelson had conjured one.

Arsenal could have felt faintly good about clawing parity from two goals down against a Bournemouth side that, against all odds, had led for most of the game. But in reality a draw was never going to satisfy: it would have tilted the balance and momentum back to Manchester City, cutting their lead to three points. When Martin Ødegaard stepped up to take their 17th corner, with the seventh minute of added time almost up, the truth was they needed something.

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How Nelson delivered it. He had already made an impact in his first Premier League appearance since November, teeing up Ben White’s equaliser moments after coming on. Now, as Marcos Senesi’s headed clearance reached him on the 18-yard line, a player who receives few chances to impress had split seconds to get everything right. His chested control was neat enough and, with nobody in attendance to challenge, there was time to create an angle for his left foot. The final action, and by far the most difficult, was a ripping half-volley that seared past a diving Neto and sent a corner of north London into meltdown.

Bournemouth’s players crumpled into assorted heaps; Arsenal’s hurled themselves around ecstatically, knowing episodes like this can decide everything. There was barely time for the visitors to restart and perhaps that was a blessing: they had scored within 9.11 seconds of kicking the match off and, back then, it seemed a tall order for the occasion to generate a more noteworthy talking point.

Nelson’s goal blasted it out of the water and, while the precedent of Manchester United is hardly one to air lightly in these parts, it had the feel of that defining afternoon in 1993 when Steve Bruce downed Sheffield Wednesday and made the end of a 26-year drought feel almost certain. Arsenal’s dry spell has not been quite as severe but they will surely feel the stars are aligning for them to end it in the next three months.

Although beloved of Arteta since he spotted the then teenager’s talent in his own playing days, Nelson had never quite caught light at Arsenal. He scored twice against Nottingham Forest in October but that was a rare afternoon in the sun; his 69th-minute deployment here came only because Emile Smith Rowe, who had earlier replaced the injured Leandro Trossard, has little in the tank. Had Eddie Nketiah or Gabriel Jesus been fit he would probably not have been involved at all.

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The centre that allowed White, who had been introduced at half-time, to aim a crisp strike that crossed the line before Neto could parry was the kind of concise action Arsenal had rarely completed. It came eight minutes after Smith Rowe had nodded an unconvincing punch from Neto back into the danger zone for Thomas Partey, ghosting in unattended, to put Arsenal back in the game. Before that point they had been running out of ideas and Bournemouth, defending stoutly but scruffily while carrying genuine threat on the counter, were on for the shock of the season.

It was little consolation to a dejected Gary O’Neil that his side had scored the Premier League’s second fastest-ever goal. The move that brought it was simple but ingenious, Bournemouth feinting to send the ball towards five players who had lined up to the left of the centre circle but instead clipping it to the right side and an open Dango Ouattara. Arsenal had been caught cold and his cross skidded under Gabriel Magalhães’ foot, Philip Billing anticipating and sweeping in from six yards.

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Neto quickly denied Ødegaard and Bukayo Saka but Arsenal were frustrated before the interval and, when Ramsdale saved from Ouattara, knew they could easily have gone in two behind. Arteta rarely rests senior players but here he had benched White and Granit Xhaka, seemingly at a cost.

When Senesi flashed a Joe Rothwell corner past Ramsdale in the 57th minute it appeared there would be plenty for Arsenal and their manager to forget. But they are becoming masters at finding a way and this may be the most significant salvage operation of all. “Everybody is overwhelmed,” Arteta said, beaming afterwards. Nelson, the unlikely hero, ensured the omens are pointing his way.