Pressure grows on Graham Potter, whose side were well beaten in a defeat that means Chelsea have now exited both domestic cups at the first stage for the first time in 34 years.
Riyad Mahrez scored a stunning free-kick and a penalty, with Julian Alvarez also netting from the spot and Phil Foden scoring in open play.
Chelsea fans chanted for both Roman Abramovich and Thomas Tuchel as the atmosphere turned toxic in the away end at the Etihad Stadium.
Nizaar Kinsella was at the Etihad Stadium to witness the action...
Kepa Arrizabalaga - 6
After Edouard Mendy broke his finger in training, Kepa continued in goal and was beaten four times. None of the goals were as much his fault as the one conceded in midweek and he made several decent saves.
Trevoh Chalobah - 5
Playing out of position at right back, Chalobah struggled at times with the pace and trickery of Mahrez who scored twice in an impressive display.
Bashir Humphreys - 5
The 19-year-old made his Chelsea debut in difficult circumstances. At times, the defence looked very ragged but he didn’t make any obvious mistakes.
Gave away a penalty and was outperformed by his teenage partner. He looked tired and struggled to keep pace with City’s attack.
Lewis Hall - 5
Still just 18, Hall looked good in possession and played out well from the back. However, he did struggle with some of City’s wing play down his flank.
Mateo Kovacic - 5
The midfielder had very little impact on the game in the first half and was substituted at half-time. It was likely a pre-planned substitution but the team got better in his absence.
Conor Gallagher - 4
The midfielder got a rare start but badly struggled badly in possession. His pressing was over committed and without quality
Jorginho - 5
The vice-captain took the armband in Azpilicueta’s absence but produced an anonymous display where he got very little of the ball.
Mason Mount - 5
After returning from injury, Mount was unable to impact the game with any of his attacking play and only looked good in the press before Chelsea suffered a huge dip in performance after the second goal.
Kai Havertz - 3
Gave away a stupid penalty with a handball in the first half and squandered a host of chances to run in behind Man City’s defence despite them playing a high defensive line. It killed Chelsea’s game plan.
Hakim Ziyech - 4
Ziyech has been unable to replicate his Morocco form at the World Cup in club colours. He didn’t create when in possession and his off-the-ball running rarely led to any chances.
Denis Zakaria - 6
As so often these days, the loanee was one of the better performers, lifting the team into a spell of dominance early in the second half. Chelsea still had little to show for it.
Cesar Azpilicueta - 6
Azpilicueta’s off-the-ball running produced one of the few transitions that threatened Man City. However, it was too much to ask him to change the game.
Omari Hutchinson - 5
The 18-year-old showed glimpses of the quality that he has shown in academy football. Unfortunately, he has had to make his first steps in the men’s game in chaotic circumstances and has not done himself justice.
Carney Chukwuemeka - N/A
David Datro Fofana - 6
It was all too much to expect the £8.6million signing from Molde to make an impact on his debut. He struggled to get on the ball as Chelsea were well beaten.
Unused subs: Bettinelli; Cucurella, Badiashile, Thiago Silva.