As with Elvis Presley's death or the Moon landing, those who care about Manchester City can recall where they were and what they were doing when a billionaire sheik from Abu Dhabi radically rerouted the trajectory of their football club and threatened to darken Alex Ferguson's twilight years as manager of rival Manchester United.
City for years was Manchester's other team, the poor cross-town cousin who could only look on with envy and sadness as United bounced from victory to victory under Ferguson and, on the back of his triumphs, built a global, money-spinning brand that sells from Beijing to Baltimore and beyond.
To be a City fan required large amounts of loyalty and no small amounts of masochism and good humor. Former manager Peter Reid recalls that the club was so threadbare that he once paid for a team hotel with his own credit card. When Ferguson was leading United to the final of the 1999 European Cup, City was mired in the purgatory of English football's lower leagues. Five months before United was crowned king of Europe, City sunk to its lowest league position ever, knee-deep in England's third tier.
Yet its fans still attended matches in droves, taking defeat on the chin and rolling their eyes at ''typical city.'' While United fans gleefully rubbed their hands, City supporters crossed fingers and hoped for better days.
One sheik and hundreds of millions of dollars later, their wait is over.
For the first time in a generation or more, the United vs. City match this Sunday - the so-called ''Manchester derby'' - will be a true contest of equals.
When referee Mark Clattenburg blows his whistle, City will field 11 players who, pound-for-pound, can match United's star-studded line-up for talent and experience.
They've already proved that by building a 2-point league lead over United before this game. That could grow to 5 points if they win. Sunday could be so important in determining whether United or City wins the Premier League next May that Ferguson described it as ''a six-pointer'' - a game that counts double.
In short, after so many years of more downs than ups, City fans now find themselves in a wondrous place.
''To say we've been on a roller coaster is a great term, really,'' City's life president, Bernard Halford, said in an interview. ''We really went through the mill.''
''It's not the easiest thing in the world when you're in the same city and one side is very successful,'' explained Mike Summerbee, who played nearly 450 times for City in the 1960s and '70s.
''You go to work everyday, you bump into people who are there every day - from the opposition, Manchester United supporters,'' he added.
But now at City, ''there's a bounce about the place.''
In City's gleaming offices, with their deep sofas, easy lighting and glassed-off spaces, there is the heady scent of revolution and money in the air. People speak with genuine awe and thanks about how the almost bottomless wealth of Sheik Mansour Bin Zayed Al Nahyan is transforming the club he snapped up in 2008 and allowing its supporters to dream seriously about knocking United off its pedestal.
At times, the sheik is talked about in almost quasi-religious terms. Halford spoke of club employees ''spreading the gospel on behalf of the sheik'' and said: ''He's not just creating a football team, he's creating a dynasty of warmth to people.''
He recalled how jubilant supporters drove around City's stadium, beeping their car horns, when the club flexed the financial clout of its new savior to buy star Brazilian forward Robinho for a British-record 32.5 million pounds (then $58.5 million) in 2008. Halford said that purchase was ''the marker in the sand that we've now got money to go and buy players and compete.''
Summerbee was playing golf that day when the news broke. ''You can imagine what it was like. The concentration on playing golf was out of the window,'' he said in an interview. ''Everybody was in disbelief, really.''
A member of the Abu Dhabi ruling family, the sheik has only attended one City match, against Liverpool last season. Halford said he'd never heard of Sheik Mansour and ''neither had the staff'' before he bought the club. But everyone in English football knows who he is now, even if they rarely see him.
With lucrative wages and promises of success to come, City has lured a multinational mix of players with big reputations and big egos who this season actually look more like a team and less like a mismatched fantasy football squad of mercenaries. They won the FA Cup this May, forcing United to take down the banner at its stadium, Old Trafford, that celebrated the number of years since City last won a major trophy. The annually updated taunt had reached ''35 years.''
City officials refuse to say how much Sheik Mansour has invested. British newspapers say the bill, including buying the club and new players and paying their wages, has exceeded 1 billion pounds ($1.5 billion). City's last annual report showed losses of 121 million pounds (then $191 million) and 133 million pounds (then $210 million) of spending on wages in the sheik's first full year of ownership.
''If you've got lots and lots of money, you're going to invest it in something,'' said Halford. ''What's happened here in the last three years is phenomenal.''
Or frightening, depending on your point of view. City's new money has met some institutional resistance from football's old powers. A year after Sheik Mansour's takeover, European football boss Michel Platini got the organization he leads, UEFA, to accept the idea that ''financial doping'' threatens to ruin professional football. For UEFA, that means clubs shouldn't live off handouts from sugar daddies and not spend more than they earn.
Whether City will manage to limbo under the new restraints on reckless spending and whether UEFA will really be able to enforce them are both open questions. City might be gambling that between now and when the rules really bite, its team will have done so well on the field that UEFA won't dare throw it out of European competition if it breaks the regulations. City also will be hoping that on-field success is bringing in sufficient riches, new sponsorships and other wealth to make its balance sheet more acceptable to UEFA.
After so many years being outspent and outshone by United, billionaire-owned Chelsea and others, those on Manchester's blue side of town feel that it's only fair that their turn has now come.
''It's jealousy'' Halford said. ''We've had to live with that with these other clubs for 10 years.''
City officials also stress that Sheik Mansour isn't investing solely in stars and trying to win matches, pointing to grandiose plans for a training academy for 400 young players the club wants to build next to its stadium. Workers are clearing and cleaning the polluted land that used to be home to a chemical plant, an alkali works, a forge, railway yards and waste dumps.
''Michel Platini should come and have a look at what's going on and see what's going to happen in the next few years, the redevelopment of the area using all local people, local businesses. This is what people don't understand,'' said Summerbee, who now works as an ambassador for City. ''If people want to develop an area, want to develop a football club, and they can afford to do it, fair enough.''
For Ferguson, who turns 70 this year, City's phoenix-like rise could ruin his remaining years at United. But to do that, his rivals - the ''noisy neighbor,'' he has called them - must turn their petrodollars into on-field domination. That is a big, big task. Since Sheik Mansour's takeover, City has not yet beaten United in a league game. One reason why Sunday's match is so important is to gauge how much closer City has edged to United.
''It's probably the biggest derby ever,'' Summerbee said. ''It's nice to be be called the noisy neighbors. ... It's nice to know that they're taking notice of us.''
''The noisy neighbors may be about to start to blow the roof off,'' added Halford.
Or the two clubs could grow side-by-side. The combination of City's ambition and wealth and of United's commercial success and winning tradition is increasingly giving Manchester the feel of being the center of England's football universe. Fittingly, a multistory football museum with interactive exhibits is due to open here next May.
''There's a buzz around the city,'' said Bryan Robson, who played in 461 games for United in the '80s and '90s, scoring 99 goals. ''It's great for Manchester as a city. If football is booming in your city, business seems to be better, people - I don't know - they just seem more jolly.''
''I don't see it as, you know, a fall of an empire and the rise of another one,'' added Reid, the former City manager in the early '90s. ''I think it's two empires, in one city.''
John Leicester is an international sports columnist for The Associated Press. Write to him at jleicester(at)ap.org or follow him at twitter.com/johnleicester