Conventional wisdom had it that the league title would be decided at the Etihad next Wednesday but Arsenal may have effectively handed it to Manchester City five days ahead of schedule.
This was almost the greatest fightback their stadium has seen, better still than the overhauling of Bournemouth, but despite pulling level late on against a brave, shattered Southampton a draw was not really enough.
Shocking defending early on helped Carlos Alcaraz and Theo Walcott, who both finished superbly, put Saints two up before Gabriel Martinelli appeared to begin restoring the natural order.
Duje Caleta-Car scored a smash-and-grab third after the break and, even though Martin Ødegaard curled in late on and Bukayo Saka dramatically equalised, Arsenal counted a heavy cost.