Manchester City could not play through the pain barrier. As their run of 32 Premier League matches unbeaten came to its end, they creaked. Ageing, tired legs were asked to chase – in vain – an opponent full of energy and a belief so rarely in evidence against the serial champions. For once, City fell short.

Make no mistake, Bournemouth were brilliant, their victory wholly deserved, with Antoine Semenyo dazzling. He demoted Kyle Walker to the doghouse, City’s captain left with twisted blood by the Ghanaian.

To be even-handed to Walker, he had answered his manager’s call when his fitness was probably far below the desired level. City’s starting selection bordered on the awesome but masked the depth of the casualty list. The bench even featured Kevin De Bruyne, unseen since September, and Savinho, who tearfully departed the field at Tottenham in midweek on a stretcher. Neither came on, even when emergency beckoned.

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Bournemouth were determined to catch City cold. They flew at the contest, right from the first whistle. Ederson had already been asked to make a spectacular double save from Semenyo and then Justin Kluivert before the scoring began when Milos Kerkez, overlapping down the left, blazed past a dozing Phil Foden, laid up Semenyo. Josko Gvardiol was brushed off, and the Ghanaian’s spin and shot beat Ederson all hands down.

Dominant from those early moments, Bournemouth’s lead was entirely deserved. City’s midfield exchanges were compressed by the energy of their opponents. Bar one Erling Haaland rampage, City offered little. With arms crossed, Guardiola muddied his black leather brogues as he paced the sidelines. Alongside him, Andoni Iraola, a coach whose upward trajectory makes him a leading contender to succeed the Catalan, was kicking every ball.

Beating Guardiola represented history; Bournemouth had never previously beaten City over 21 previous meetings. The last time a point was collected was 1999, in the third tier, when Joe Royle was City manager and Shaun Goater led the line.

Could it happen? Kerkez continued his eye-catching afternoon with a last-man block when Bernardo Silva had the goal gaping. Home confidence began to flow as Bournemouth dominated space, and there were jeers when Haaland, in attempting his own turn and shot, fired wide. In doing so, he appeared to roll his ankle but saw out a first half that concluded with Bournemouth putting together an almost endless sequence of passes. Their lead might well have been greater than a single goal from an outstanding 45 minutes. Few teams have dominated City midfield’s in such a fashion.

Haaland came out for a second half where Bournemouth set off after another fast start. Semenyo took down a long ball, only for Evanilson to steal in and force another Ederson save when Mark Travers, Bournemouth’s stand-in keeper, had yet to be called into action.

Signals of a possible City revival began to sound. Haaland was penalised when jumping highest for a header and Foden drifted a effort wide after Matheus Nunes had beaten Adam Smith with pace and trickery. Walker, closest to his manager and struggling badly with Semenyo, was given constant, terse, advice from the sidelines and eventually switched to centre-back.

Tempers began to fray when Lewis Cook, Bournemouth’s ratter supreme, took out Haaland with a trailing leg and the City striker, after much delay, again resumed. That Bournemouth began to retrench at the hour mark suggested a game of one-way traffic, only for the counter to be triggered in devastating style. Semenyo, again, blew past Walker, and supplied Kerkez, whose low pass found Evanilson, the striker hooking the ball home.

The lead might have stretched further when Marcus Tavernier cracked the inside post. Could they hang on? Travers failed to claw away Gvardiol’s header from Ilkay Gündogan’s cross and a closing 10 minutes of tension were set up. Jérémy Doku’s dribbling was added to the mix, and the Belgian forced a save from Travers ahead of six extra minutes being added on.

Chaos duly ensued, Travers making another save, from Haaland, the ball somehow not crossing the line as the striker next struck the woodwork with his follow-up. Foden slapped a shot wide but the champions – ragged, exhausted, dumbfounded – could give no more.