Match ends, Manchester City 1, Chelsea 3.
Chelsea's eighth successive Premier League win cemented their place at the top of the table - but their victory at Etihad Stadium ended in chaos as Manchester City's Sergio Aguero and Fernandinho were sent off in injury time.
Antonio Conte's side delivered an impressive statement of intent as they cut City apart on the break after going behind to Gary Cahill's own goal on the stroke of half-time, when he diverted Jesus Navas' cross beyond keeper Thibaut Courtois.
The game turned on Kevin de Bruyne's 56th-minute miss with City in control, crashing Navas' cross against the bar from inside the six-yard box.
Chelsea were level on the hour when Diego Costa outmuscled Nicolas Otamendi to score and they were ahead 10 minutes later when substitute Willian raced clear to beat City keeper Claudio Bravo with ease.
Eden Hazard completed a magnificent win for Chelsea with another goal on the break, showing too much pace for Aleksandar Kolarov to wrap up three vital points.
- Answers from Conte; questions for Guardiola
- Guardiola apologises after mass brawl
- Clinical Chelsea punished Man City - Waddle
Chelsea send powerful message
Chelsea's renaissance since a 3-0 loss at Arsenal in September left them in eighth place, eight points behind then leaders City, has been hugely impressive - but this is their most powerful statement of the season.
Eight wins from eight and only two goals conceded tells the story and this win against City was the second week in succession they have come from behind to beat a team that could be regarded as realistic title rivals after overcoming Tottenham at Stamford Bridge last weekend.
They were tested by periods of City domination, but showed a ruthlessness to match their steely resilience and tore Pep Guardiola's side to shreds in the closing 20 minutes.
Conte's switch to a three-man defensive system and the rejuvenation of key men such as Costa and Hazard is making this Chelsea side resemble the full title package.
Guardiola's defensive chaos
Manchester City have kept one clean sheet at home in the Premier League this season - in the 4-0 win against Bournemouth - and on this evidence it is easy to see why.
For all City's domination of possession and creation, Guardiola's side have an Achilles heel at the back that was ruthlessly exposed here.
Yes, De Bruyne should have put the game out of Chelsea's reach but City's defence offered the visitors hope throughout - and how they capitalised when given the chance.
Guardiola has been linked with defensive reinforcements, particularly Southampton's Virgil van Dijk, and the manner in which they were dismantled here now makes this a matter of urgency.
The jitters started early when John Stones was caught in possession in his own area, while defensive partner Nicolas Otamendi had a nightmare afternoon and was culpable for Chelsea's first two goals from Costa, where he was weak in the challenge, and Willian.
Guardiola gestured in despair towards his central defenders after Willian's goal - his displeasure will surely take the form of more decisive action in January.
An unsavoury end
It is unlikely either Manchester City or Chelsea have heard the last of a shameful conclusion to a high-class game of football as players and officials from both sides became embroiled in ugly scenes.
City's frustration at what they believed were a series of injustices at the hands of referee Anthony Taylor boiled over in injury time as Aguero caught Luiz high and late, which happened after the Argentina striker clashed with the defender at a corner earlier.
Chelsea's Nathaniel Chalobah joined in and was lucky not to see red, while Fernandinho was sent off for grabbing Cesc Fabregas.
Even then, Fernandinho had to be forced to leave the pitch and with the whole situation threatening to go completely out of control, it was fortunate referee Taylor was able to blow the final whistle seconds later.
It is hard to see how both clubs can escape censure for a failure to control their players.
Man of the match: Eden Hazard (Chelsea)
Chelsea win eighth game in a row - the stats
- Chelsea have won eight consecutive Premier League games for the first time since the 2006-07 season, when they won nine in the row during Jose Mourinho's first spell as manager.
- Manchester City lost a Premier League home game that they have been leading for the first time since April 2009 (1-3 v Fulham).
- Since the start of 2013-14, Chelsea striker Diego Costa has scored 70 goals in 103 league appearances (Premier League and La Liga combined).
- City have kept a clean sheet in just two of their 14 Premier League games under Pep Guardiola.
- Manchester City made six changes to their starting XI from their previous Premier League game (v Burnley) - they have made 46 starting XI changes overall this season, more than any other club.
What they said
Manchester City boss Pep Guardiola on Sky Sports: "Congratulations to Chelsea - they won. We played really good, had a lot of control and created chances - but the ball in the box was not strong enough.
"Chelsea's approach was really different but that is part of the game. You don't expect Chelsea to create 25 chances - they created three and scored three."
When asked about Aguero's challenge on Luiz at the end of the game, Guardiola added: "Both players were strong there - that's all."
Chelsea manager Antonio Conte on Sky Sports: "Today was very tough and the game was open until the end. There were lots of chances for both teams to score.
"I saw lots of character from my team and that's very important to grow - but we must continue to work and improve."
Speaking about Costa's role as peace keeper at the end of the game, he added: "Diego is showing he is using his passion in the right way and I'm very happy about that."
Jason Roberts, former West Brom striker, on Final Score: "Chelsea were incredible. They went behind but they kept their heads. I think Pep got it wrong and I think Conte got everything right.
"The performances from Willian, from Costa, from Fabregas - who came on and showed he has that bit of guile. This is the best game I've seen this season."
Manchester City have a home game against Celtic in the Champions League on Tuesday (19:45 GMT kick-off), followed by a Premier League trip to Leicester City on 10 December (17:30).
Chelsea's next game is a home match against West Bromwich Albion in the Premier League on 11 December at 12:00 GMT.
- 30OtamendiBooked at 17mins
- 24StonesSubstituted forIheanachoat 78'minutes
- 15NavasBooked at 81mins
- 25FernandinhoBooked at 90mins
- 8GündoganSubstituted forY Touréat 76'minutes
- 19SanéSubstituted forClichyat 69'minutes
- 17De Bruyne
- 10AgüeroBooked at 90mins
- 42Y Touré
- 30David Luiz
- 7KantéBooked at 49mins
- 4FàbregasBooked at 90mins
- 11PedroSubstituted forWillianat 50'minutes
- 19Diego CostaSubstituted forChalobahat 85'minutesBooked at 90mins
- 10E HazardSubstituted forBatshuayiat 90+4'minutes
- Anthony Taylor
- Shots on Target
Second Half ends, Manchester City 1, Chelsea 3.
Delay over. They are ready to continue.
Cesc Fàbregas (Chelsea) is shown the yellow card.
Nathaniel Chalobah (Chelsea) is shown the yellow card.
Fernandinho (Manchester City) is shown the red card for violent conduct.
Delay in match David Luiz (Chelsea) because of an injury.
Sergio Agüero (Manchester City) is shown the red card.
Foul by Sergio Agüero (Manchester City).
David Luiz (Chelsea) wins a free kick in the defensive half.
Substitution, Chelsea. Michy Batshuayi replaces Eden Hazard.
Attempt saved. Willian (Chelsea) right footed shot from the right side of the box is saved in the bottom left corner. Assisted by Eden Hazard.
Attempt missed. Yaya Touré (Manchester City) header from the centre of the box is high and wide to the left. Assisted by Kevin De Bruyne with a cross.
Goal! Manchester City 1, Chelsea 3. Eden Hazard (Chelsea) right footed shot from the centre of the box to the bottom left corner. Assisted by Marcos Alonso with a through ball following a fast break.
Attempt missed. Kelechi Iheanacho (Manchester City) right footed shot from outside the box is high and wide to the right.
Hand ball by Eden Hazard (Chelsea).
Corner, Manchester City. Conceded by César Azpilicueta.
Foul by Aleksandar Kolarov (Manchester City).
Eden Hazard (Chelsea) wins a free kick in the defensive half.
Attempt missed. Kelechi Iheanacho (Manchester City) header from the left side of the six yard box is high and wide to the left. Assisted by David Silva with a cross following a corner.