Saturday marks exactly 10 years since Manchester's football landscape changed, when the so-called "noisy neighbours" ended up partying on their local rivals' pristine front lawn.
Instead, it has had lasting significance for both clubs, and not just because the margin of City's victory at Old Trafford would eventually see them clinch that season's title on goal difference, ahead of Manchester United.
This was a day that signalled the start of a power shift that has defined the past decade in the city and beyond, with the Blues beginning their land-grab on Red territory, and in spectacular style.