It was end-to-end stuff in the first period, with opportunities for David Silva, Eden Hazard, Fernandinho and Sergio Aguero before Gary Cahill's own goal right at the end.
It was turned up a notch in the second period, with excellent opportunities for Kevin De Bruyne and Aguero. However Antonio Conte's side took over from there with goals from Diego Costa, Willian and Eden Hazard securing their eighth win in a row. It didn't end there with dismissals for Aguero and Fernandinho in extra-time to round-up an excellent afternoon of football.
It was expected to be a huge clash at the Etihad Stadium, with both sides gunning for the Premier League table, and the opening proceedings of the game didn't disappoint.
Referee Anthony Taylor was called into the action eight minutes in, when Silva cut back on Cahill with his trailing arm taking it out of play, but the referee waved away any appeals.
The visitors were handed a golden opportunity in the 15th minute, young star Leroy Sane gifted an opportunity to Hazard, but the Belgians' effort was just a yard wide of Claudio Bravo's post.
The fans were in frenzy in the 25th minute, when Fernandinho rose highest to bury De Bruyne's free-kick into the bottom corner, but the Brazilian's effort was flagged offside.
Taylor was called upon once again on the half-hour mark, when Cesar Azpilicueta's short back-pass was latched upon by Aguero. David Luiz stepped across the Argentine bringing him down, however despite the negative response from the Etihad faithful played was waved on.
It looked like that both sides would go into the break goalless, but Pep Guardiola's side found themselves ahead just before the break after a comical error.
Jesus Navas managed to get ahead of Marco Alonso, and put a dangerous ball into the six-yard box. The usually responsible Cahill got tangled up and managed to turn it into his own net, only the second goal against the Blues in the last eight matches.
The start of the second period was no different to the first, as both sides came flying out of the traps with some great opportunities. The first came just four minutes after the restart, when Taylor played advantage as Sane stormed forward. The German played it through to De Bruyne, and he was one-one-one with Thibaut Courtois, but his compatriot did well to deflect it away with his leg.
It was then the turn of City, as Aguero sneaked in on Alonso's backpass. The striker managed to get between Courtois and Cahill, but the defender did well to block on-the-line.
Made to regret miss
City should have made it two in the 57th minute, Navas blazed down the right before finding De Bruyne in the middle. It looked more difficult for the Belgian to miss, as he was four yards out, but he clattered it against the crossbar.
After De Bruyne's golden chance, Conte's side stepped into gear, and found themselves ahead three minutes after they should been two goals behind. It was a beautiful ball over the top from Cesc Fabregas was perfect for Costa, the Spaniard did brilliantly to shrug off Nicolas Otamendi before putting it past Bravo.
Chelsea continued to turn the screw after getting back into the conquest, and they rounded up the three points as the clock ticked down with some devastating counter-attacking football.
İlkay Gündoğan was dispossessed in the 70th minute and the Blues broke with lightning pace. Costa did well to roll Otamendi before playing it into Willian who managed to pick out the far corner of Bravo's goal.
It was game over as the clock ticked into extra-time, as Chelsea added their third and final goal of the afternoon. It was another quick counter-attack as Alonso's clearance was picked up by Hazard. The Belgian beat Aleksandar Kolarov for pace and smashed it home.
Loss of heads
It looked like the drama would be wrapped up for the afternoon at the Etihad, but there was one final twist in the tale as City were reduced to nine men.
It all came from Aguero's horrific knee-high tackle on Luiz, which he was sent off for. The tackle sparked a clash which ultimately ended with Fernandinho pushing Fabregas over the advertising hoards which Taylor dismissed him for to end an excellent afternoon at the Etihad.