Gentlemen, start your engines.

Chelsea stunned Manchester City 1-0 on Monday to turn the Premier League title chase into a three-team race behind a superb goal from defender Branislav Ivanovic. This was no smash and grab, nicked out of Jose Mourinho's famous "parking of the bus:" it was a full-throttle race forward that exposed City's back line and out-did the league's highest-powered offense at their own game.

Chelsea hit the woodwork three times in this game, and inarguably should have added a goal or two more to their tally. In contrast, the normally high-firing City were limited to just three shots on frame, a surprisingly low amount for a side that has scored more goals at this stage of the season than any other side in the Premiership's history.

City were held at bay all night in historic fashion. Consider also that City -- a team that had just come off a 5-1 beat down of Tottenham at White Hart Lane -- were held scoreless at the Eithad for the first time since November 2010, a 62-game stretch. City had not dropped a match at home in their last 13 games. And despite having three key players out injured for the match, they were widely considered the superior side heading into this game, a seemingly unstoppable sky blue wave that washed all opponents away.

That may now have to be rethought in the wake of this match, a textbook example of ferocious defense and counter-attacking acumen. Mourinho, employing two holding midfielders in front of his back four, allowed four men to lope forward into space, putting intense pressure on City's back line. This opened up huge gaps in the middle of the field that City should have been able to race into - but the lack of a speedy pivot man denied them of the opportunity to exploit them.

Video: Pellegrini: Loss not decisive for City

The key absentee proved not to be the sidelined Sergio Aguero, City's on-fire -- but oft-injured -- striker. Instead, when the lineups came out, it was the omission of Fernandinho that raised eyebrows. Apparently injured in their last match, his absence forced Yaya Toure to stay back - and forced manager Maneul Pellegrini into a gamble that backfired: moving the redoubtable but slow Martin Demichelis into midfield as cover.

Demichelis, normally deployed as a central defender, never looked comfortable, and his passes lacked the crispness and pace to spring his side forward. His inability to keep up with the speedy Willian and Eden Hazard piled more pressure on the heart of the City defense, with Vincent Kompany constantly being pulled out of position in an effort to stem the tide.

And every time City tried to range forward and use Aleksandar Kolarov and Jesus Navas on the opposing flanks to pry the Blue apart, Chelsea cleverly forced them to cut inward instead, blunting their firepower. City's attempt to work the overload on the left flank failed, with David Silva missing two fine chances from close range, and the space left allowed Willian and Hazard to storm down the field with impunity.

Ivanovic's goal might have been fluky -- a left-footed shot to the far corner from a normally right-footed player, and on a half-volley -- but there is no mistaking that it resulted out of quality buildup and incision. Ramires had been denied just moments earlier off a four-on-two break that Joe Hart had bravely smothered, and was stopped again after Kompany was forced to go to the floor to block his shot away. The rebound fell to the Serbian, who fired a low rocket past the despairing keeper.

Mourinho could have chosen to close up shop, but sensing the nerves and weakness on display, kept pushing his waves forward. It wasn't until late in the game, when there was a clear sense that City wouldn't be able to buy a goal on the night, that his Blues resorted to their game-killing ways.

Both teams have some luxury ahead in the league: Chelsea face Newcastle and West Brom , while City play Sunderland and Norwich . They are expected to win these games -- while leaders Arsenal get to face Liverpool and Manchester United back to back. For some reason, everyone expects the Gunners to drop points in this period - and if they do, these two sides will be waiting to pounce.

Yet these two will face each other again soon, in a key FA Cup tie in just under two weeks' time, again at the Etihad. Pellegrini is likely to have Fernandinho back then, and his team will surely learn the lessons offered up here tonight.

But the damage has been done. City are no longer invincible at home, and it is scrappy, boring and often-dirty Chelsea that are on the rise. It is a riveting race, this. Game on, gentlemen. Game on.