From a little pocket of travelling fans in the corner of Kingsmeadow came a cascade of roars and screams, the sound of a title race coming alive. For Manchester City, a statement result to match a statement performance. The queens of Kingsmeadow have been dethroned, Chelsea beaten at home in the Women’s Super League for the first time in more than three years, their lead cut down to nothing: zero points, zero goal difference.

Khadija Shaw got the only goal of the game, her first against Chelsea in the league in five attempts, but really this was a tale of resolve and defensive backbone in the face of almost unimaginable pressure. Not just the increasingly desperate waves of Chelsea attack but the burden of history, the weight of what this would all mean.

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And it meant the world: you could see that as City’s jubilant players celebrated with their fans at the end, still too pumped with adrenaline to feel the weary legs and budding bruises from a brutal night’s work.

Most impressive of all was the way they protected the inheritance Shaw gave them early on. The City back five were immense: Laia Aleixandri regal in the duel, Alex Greenwood valiantly holding her own against the threat of British-record signing Mayra Ramírez, even if she was fortunate not to give away a penalty in the first half. Best of all, perhaps, was their teenage goalkeeper, Khiara Keating: surfing a wave of good form, a ball of skittish energy, making a crucial double save in injury time.

You could go on through the spine of the team: Yui Hasegawa at the base of midfield, Jess Park in between the lines, the way Shaw was as pivotal in defence as she had been earlier in attack. And if the denouement felt a little sketchy and chaotic, to an extent City had earned their little strokes of luck. For all the pressure they would inevitably impose in the closing minutes, you would still struggle to identify more than one or two clearcut chances that Chelsea created all game.

Ramírez was a nuisance up front and in the channels, but Fran Kirby in a slightly wider role was uncharacteristically quiet and so was Lauren James.

A week of feverish speculation has ended in the worst possible way, and for all the talk of who will succeed her, Emma Hayes will know that minds need to be focused on the present, on the fine margins that will decide the fate of this title.

Like the one upon which this game ultimately turned. And fittingly, it was a turn: 13 minutes had passed when Erin Cuthbert tried to swivel on the ball in her own half, failing to spot that Park was closing her down at speed. Park robbed the ball, her pass to Shaw was perfectly weighted, and the finish was pure silk: outside of the foot, lifted carefully over the onrushing Hannah Hampton, the hand cupped to the ear in celebration before the ball had even hit the net.

City could quite conceivably have finished the game in those first 20 minutes. Shaw had another fine chance a couple of minutes later, and then another shortly afterwards when she shot straight at Hampton. But as the half progressed Chelsea began to assert themselves, James picking up the ball in more threatening positions, the midfield slowly learning the manner and movements of Ramírez.

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They should probably have had a penalty on the half-hour when Ramírez burned Greenwood around the outside for pace and then stumbled on the ball. A fraction of a second later Greenwood steamed in with a sliding tackle that got absolutely zero ball and a significantly non-zero portion of leg. The referee, Abigail Byrne, was unmoved, and in an age when pretty much every officiating controversy is either bias or corruption, perhaps this was a decision that could safely be filed away as a honest error. Albeit, a pretty bad one.

City did sporadically threaten in the second half. Perhaps Chelsea’s injury-time equaliser against them in October was a bleak reminder of the dangers of over-caution. But it was Chelsea who enjoyed the weight of chances: Cuthbert going agonisingly close with 78th minute, Keating saving from Jelena Cankovic in the 95th, and then brilliantly smothering the follow-up from Sjoeke Nüsken.

A weird and unfamiliar sensation gripped Kingsmeadow at full time. City have gone a little under the radar this season, but there will be no hiding places now. Eight games remain: Chelsea have marginally the tougher set of fixtures, with a trip to Manchester United on the final day of the season, along with the demands of the Champions League. It’s becoming increasingly clear that in order to give Hayes the sendoff she deserves, Chelsea are going to need to wring out every last remaining drop of her genius.