Antonio Conte's Chelsea are remarkably ruthless and bloody-minded - they look like champions

After the magnificent seven, the great eight. Chelsea’s winning run goes on and grows more remarkable. They lost virtually every measurement – shots, possession, territorial advantage – but not their tradition of triumphing or their impeccable run of results since Antonio Conte changed shape and their season. They inflicted Pep Guardiola’s first defeat at the Etihad Stadium with a demonstration of ruthlessness, a bloody-minded refusal to be bowed and the sense that the ends justify the means that Conte has imported from Serie A.

Manchester City, meanwhile, lost not merely a match, but their composure. Sergio Aguero and Fernandinho’s injury-time dismissals, one for an outrageously late tackle on David Luiz, the other for needlessly grabbing Cesc Fabregas by the throat, symbolised how a game that was progressing according to plan ended in chaos and controversy. Both will miss another potential title decider against Arsenal. City could come to rue Chelsea’s powers of recovery still further.

Their punishment will continue. The league leaders’ immediate reward is a four-point advantage over City, and the unequivocal status as favourites in the title race. They are a team who will take some stopping. They illustrated as much on a day when much went wrong and they still prevailed. Even as they conceded in comical fashion, they highlighted that City have the greater defensive problems. They are more liable to be caught on the counter-attack and have supposed stoppers like Nicolas Otamendi, who fail to justify hefty price tags and look fallible when isolated one on one.

The defining figure of a seminal game was Diego Costa, who powered past Otamendi to equalise, set up Willian’s strike and eventually hobbled off after a masterclass in Machiavellian striking. He ensured that, for the second successive week, Chelsea won having trailed. For the first, they won without one of the pillars of Conte’s defensive system.

Fabregas started because Nemanja Matic was injured, recalled when he had been rejected. Where Conte’s first choices charge around the midfield, Fabregas chugs. Yet he possesses other attributes. His ability to pick a perfect pass once prompted Guardiola to buy him. From the quarterback role, he picked out Costa to level.

Then scorer turned creator. Costa played the defence-splitting pass from the centre circle. Willian broke clear to angle his shot beyond a static Claudio Bravo, whose tendency to watch efforts rather than saving them is looking a distinct drawback. Meanwhile, Aleksandar Kolarov, having failed to halt Willian, abandoned his attempt to stop Eden Hazard as he raced clear for the 90th-minute third.

It was enough to explain why City have only two clean sheets in the Premier League this season. They are a side with a soft underbelly, one who undermined their excellent work with profligacy and poor defending. Guardiola unlocked Conte’s 3-4-2-1, aided by a pressing game played at pace, a week’s preparation and some high-class players. It counted for nothing.

The Catalan has the audacity of a dreamer and the imagination of an original thinker. It is hard to imagine anyone else playing 3-2-4-1, let alone against potential champions. With better finishing, it would have been deemed an expert dissection of a different shape. But calm heads were conspicuous by their absence, both in the injury time and the penalty box.

Instead an offside Fernandinho had a goal disallowed, City were denied one, perhaps two, penalties, David Luiz escaped a potential red card, Kevin de Bruyne and Aguero were denied by Thibaut Courtois and, crucially, the former Chelsea midfielder hit he bar at 1-0.

City’s pressure produced a solitary goal. Chelsea creaked before they cracked. Jesus Navas has been hitting the first defender in the penalty area with crosses for years. A plan finally paid off. Cahill attacked it with the wrong foot, hooking the ball beyond a helpless Courtois. In an instant, Cahill reverted to his error-prone form of September. In a dreadful misjudgement, Chelsea conceded only a second goal in 725 minutes of Premier League football.

The notion they possessed an impenetrable, impeccable defence was dented. They erred too often, Cesar Azpilicueta with an under-hit back-pass that Aguero probably would have met but for David Luiz’s illegal intervention, Marcos Alonso with a blind ball back that the Argentinian did meet; Cahill, alert and aware this time, cleared off his own line.

What they had was spirit in abundance. It was illustrated by Pedro, a revelation as an inside-right of late, materialising in the left-back role to hold off Aguero. Or Azpilicueta, materialising from nowhere to block the Argentinian’s shot. An aberration brought the right response from Chelsea. A capitulation brought the wrong one from City.