Deep into eight minutes of added time the ball fell to Reiss Nelson, Arsenal’s man for a fairytale moment, and the Emirates fleetingly braced itself to do it all again. Their players had levelled from nothing against a fine, dogged Southampton but a draw would be little better than a defeat for their title hopes. Now the crowd were willing them towards the North Bank goal and, as Nelson took aim near the edge of the box, they prepared for the most thrilling act of deja vu. This time Nelson shot just wide, a deflection off James Ward-Prowse diverting the effort off target, and Arsenal would not come close any more. There was to be no repeat of the heroics that steered their rollercoaster past Bournemouth last month: given they were 3-1 down in the 88th minute here it would have been their most spectacular salvage operation yet, but they had set themselves too steep a task and will probably count a heavy cost. Amid the noise after Nelson’s crushing of the Cherries, a vocal minority had cautioned that Arsenal’s penchant for enjoyable chaos might not lend itself to a successful pursuit of top spot. The team’s offering here felt like the logical end point of that argument: the game was far beyond their control within 14 minutes of the start, excellent finishes from Carlos Alcaraz and Theo Walcott made possible by some truly rank defending, and from then they were always scampering uphill. If they were too measured in allowing Liverpool and West Ham to overhaul them in the previous two games, now Arsenal were impossibly helter skelter. On paper this had appeared an ideal throat clearer before what, at least before kick-off, was billed as Wednesday’s likely title decider at the Etihad. But after 26 seconds Arsenal had any over-confidence rammed down their gullets, Aaron Ramsdale miscuing what should have been a straightforward pass from his own penalty area and allowing Alcaraz an easy interception. The impressive young Argentinian still had plenty to do and he executed a slick, curling finish from 20 yards. Anyone fixated on that Bournemouth comeback might have noted that Arsenal conceded negligently early then, too, within nine seconds. But here they went two behind before they could muster much threat in response, Martin Ødegaard giving possession away in midfield and watching Alcaraz make hay again. This time a perfect slide-rule pass inside a lumbering Gabriel Magalhães told Walcott exactly what to do and he responded, sidefooting firmly across Ramsdale with the kind of strike that once endeared him to fans in these parts. Oleksandr Zinchenko gathered Arsenal into a huddle and they appeared to clear their heads, Bukayo Saka taking Ødegaard’s pass to the right byline and clipping back for Gabriel Martinelli to sweep in an impressive volley. Under a fifth of the game’s eventual length had been played and it seemed likely the natural order would be restored from here. Nonetheless Ramsdale, part of a back five that never looked secure, had to make a double save from Mohamed Elyounoussi and Alcaraz while Saints weathered most of Arsenal’s pressure. A vital defensive contribution from Alcaraz, clearing Ben White’s header off the line, ensured they went in ahead at the interval. The two-goal advantage was restored midway through a second period that had brought huff, puff, and plenty of frustration from Arsenal at Gavin Bazunu’s lack of appetite to hurry his goal kicks. Alcaraz, on a yellow card, had been sacrificed for an extra centre-back in the form of Lyanco; another defender, Jan Bednarek, had succumbed before half-time after a collision with Martinelli. Arsenal, for whom Fábio Vieira endured a frustrating night in place of the ill Granit Xhaka, saw little come off before being dealt the seemingly decisive blow. It came from Saints’ first real attack of the half, Kyle Walker-Peters making ground and earning a corner on the right. Ward-Prowse’s delivery was flicked on by Armel Bella-Kotchap and Duje Caleta-Car, who had replaced Bednarek, headed in gleefully at the far post. Arteta turned away and winced: a tense atmosphere had any remaining air sucked out of it. Southampton were on for a potentially transformative win and, bar a sitter missed by Gabriel Jesus straight after the goal, looked secure as the minutes ticked down. The Emirates was hardly pulsating with belief but then Ødegaard, with a flourish from outside the area, offered Arsenal hope and the visitors’ legs began to resemble concrete. Saka quickly swept in from a rebound and, when the fourth official’s board was held up, few in the stadium could not have envisaged Arsenal blowing the roof off again. In that chaotic added spell Leandro Trossard snicked the bar and, even after Nelson’s close call, the ball pinged wildly around Saints’ box via various calls of dubious merit for penalties. Arsenal could not be faulted for sticking to their mission but paid for making it far more complicated than it should have been. Neither set of players knew where to look at the whistle: Southampton must use this performance as a basis for a great escape but visibly saw an opportunity squandered; Arsenal fell en masse to their knees and must find new energy to achieve the improbable at City.