No wonder Pep Guardiola has ruled out ever managing Manchester United.
On this evidence, Guardiola, 48, will be a pensioner by the time United have any chance of emerging from their current malaise to challenge at the top again.
United have spent close to £1billion players since Sir Alex Ferguson retired seven years ago, but are further away than ever from reclaiming their status as the country's dominant football force.
They may have beaten City at the Etihad Stadium last month, but normal service was resumed here as Ole Gunnar Solskjaer's side were subjected to a crushing, humiliating defeat.
Not since their 6-1 defeat to City at Old Trafford back in 2011 have United looked so impotent against their local rivals, who played with brutal brilliance to dispatch Solskjaer's shambolic side.
Solskjaer called for his United players to be given greater protection from officials, but ultimately they needed protecting from themselves, their collective shortcomings ruthlessly exposed by City.
After Kevin De Bruyne left him in a twisted heap on the deck in the move that led to City's third goal, that claim from United's legendary boss seemed like a sick joke.
Such was City's dominance, it ultimately became a case of damage limitation for United, Solskajer hooking the ineffective Jesse Lingard at half-time for Nemanja Matic.
Marcus Rashford scored, but it was too little, too late.
After last month's blip at the Etihad, City reasserted their superiority, while the road to redemption looks even longer and painful for United.
