Roberto Mancini had spent much of this season reading the riot act to his Manchester City squad. The players needed to "change their mentality", drop the obsession with "days off" and not walk the kind of celebrity path that led Adam Johnson and Micah Richards to spend £12,000 at a charity auction on a joint date with Jordan.
What City really needed, though, was an earth-shaking win, preferably over title-race opponents who had played five, won five, scored 21 and conceded one in defence of their Premier League title. Mancini's sermons were put on hold as his game-changer in chief and new captain, Carlos Tevez, set off inside his own half nearly an hour into this stodgy game, jinked right to confuse Ashley Cole and drove home a shot that pierced Chelsea's invincibility.
In an interview last week Mancini said: "When people ask why do I come here, I tell them it is because Manchester City never win." He also said: "There are players whose only target is their day off and that is a big problem. You must replace them with those whose target is the win against Chelsea, then against Arsenal, then against Manchester United, who will work every day for this."
Presenting oneself as a headmaster with a shaky grasp of English to 25 multimillionaires is a risky strategy but here it paid off in the battle of the Milanese managerial aristocrats. The older Carlo Ancelotti guided Chelsea to wins against West Brom, Wigan, Stoke, West Ham and Blackpool but the champions have often been prone to complacency. When a defeat follows several easy wins there is usually a "clear the air meeting" at Cobham, with John Terry prominent, and Ancelotti may now feel that City's win will have a useful salutary effect.
For the victors, though, introspection is suspended. Sheikh Mansour is still entitled to wonder how £600m can buy so little entertainment but the esprit de corps is improving. Any side housing Nigel de Jong, the arch destroyer, and the wardrobe-shaped Yaya Touré is unlikely to shirk confrontation. But the most encouraging aspect of City's breakthrough was how they overcame Chelsea's midfield power, the force and physicality of Ancelotti's defence.
A 3-0 win against Liverpool sent expectation shooting up but then came a 1-0 defeat at Sunderland, a draw at home to Blackburn Rovers and a Carling Cup defeat at West Brom. Mancini talks of the City job less as a managerial challenge than a moral crusade. Johnson is among those suspected of losing focus. "He has to understand he must work and he must think about football every day, not other things," Mancini said. England's brightest winger was left on the bench to absorb that lesson before coming on for David Silva.
As Labour prepared to elect a new leader across town, Mancini asserted his hard-man credentials against Ancelotti's enforcers. Lacking pace and zip themselves, City clattered and crunched into contact. Dedryck Boyata, a 19-year-old centre-back pressed into service on the right of defence, displayed a precocious mastery of the dark arts, executing a rugby league neck-wrap on Didier Drogba and then body-checking Chelsea's senior striker as he tried to infiltrate a gap.
This lad brings poise, and menace, to a sometimes slow, sometimes cumbersome ensemble. The accusation that Mancini is overloading the defensive areas with three deep midfielders was partially answered by redeploying Yaya Touré slightly further up the pitch. Mancini's main aim, though, is to make City fight, not entertain. This was reflected in his team selection. De Jong, Gareth Barry, James Milner and Tevez are not pacifists. Mancini wants to transmit this toughness to Jô and Emmanuel Adebayor.
Ancelotti, whose regal bearing was acquired at AC Milan, still has a stronger hand than Mancini, who oversaw a revival in that city at Internazionale. City must apply themselves against lesser foes the way they rouse themselves against the elite. As part of his austerity drive, Mancini invokes the "four or five years" it took Sir Alex Ferguson before Manchester United's players bought into his religion. Nice try. In Ferguson's first two seasons there was no net transfer spend of £300m.
Unless this City team are rebalanced to add more attacking vibrancy City fans will continue to derive their pleasures from a strong emotional attachment to the badge. The football will not send them into raptures. But few will mind, if Chelsea are met nose?to-nose and conquered. Memories of all the bad times are still sharp enough to sustain the current gratitude.
The players will hope for a respite from the boot-camp tannoy. They will hope in vain. Mancini said here: "We must stay a long time on the top, we must win something. Just because we won this game we don't think everything is OK."
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