Few could have predicted just how drastically the balance of power in Manchester would shift in the battle for Premier League dominance.
With four consecutive titles to their name, Manchester City have established themselves as English football's dominant force.
Man United used to dominate the league, but now title supremacy has belonged to Man City
6
Man United used to dominate the league, but now title supremacy has belonged to Man CityCredit: Getty
But things haven't always been this way, with Manchester United enjoying an even longer period of supremacy before this.
While City may have triumphed in eight of the last 13 Premier League seasons, they still have some way to go if they are to match the Red Devils' remarkable 20-year era of dominance.
Between 1992 - when First Division clubs resigned from the Football League and the Premier League was established - and 2013, Sir Alex Ferguson's all-conquering sides picked up 13 league titles.
City, meanwhile, had incredibly contrasting fortunes in the early part of this spell.
Read More on Man United
As United reigned supreme, their rivals struggled, and spent three years languishing in the second and third tiers between 1997 and 2000.
And former United midfielder Nicky Butt, who was there for the early part of the domination, has admitted it made Manchester derby days incredibly enjoyable occasions for him.
Having progressed through the Old Trafford youth ranks as part of the iconic 'Class of 92', he made 387 appearances for his boyhood club between 1992 and 2004.
Speaking exclusively to talkSPORT.com ahead of the first derby of the season, Butt reflected on how different it was for the red half.
Butt, who lost just once in eight Manchester derby fixtures against City, winning five, said: “It was a fan in me that loved it.
“And not only that, we pretty much won every single one of them as well, so it was like the bragging rights when you went home.
Butt played in one of Man United's greatest sides that dominated the 1990s and early noughites
6
Butt played in one of Man United's greatest sides that dominated the 1990s and early noughitesCredit: Getty
The United academy graduate was one sixth of the Class of 92, all of whom went down as club legends
6
The United academy graduate was one sixth of the Class of 92, all of whom went down as club legendsCredit: Getty
“It’s a great day, not been so great over the last 10 years, but it was great when I was playing.”
When Butt's United were the team to beat, it was Arsenal who would run them close but it was a hard for a boyhood United fan not to get up for derby day.
Trying to describe what it was like being a Manchester lad and playing against City, he explained: “The local rivalry, the build-up of a derby game - when you've been brought up in the area and you're a Man United fan, you can't really describe what it feels like.
“I remember getting up on the day of a derby - up at 7am and the atmosphere around the area is just brilliant.
“It'd be the same with Everton vs Liverpool or Tottenham vs Arsenal, same all up and down the country, but it is a very special day, derby day."
Despite Arsenal being their biggest rivals, it was another side he'd look out for in addition to the City game.
Keane and Vieira epitomised the once fierce rivalry between United and Arsenal
6
Keane and Vieira epitomised the once fierce rivalry between United and ArsenalCredit: Getty
Butt, though, relished the battles against his local rivals having been born in the city as well as whenever Liverpool and United played
6
Butt, though, relished the battles against his local rivals having been born in the city as well as whenever Liverpool and United playedCredit: Getty
“Liverpool was the one I'd look out for at the start of every season.”
And while United often head into clashes with their bitter rivals as underdogs these days, City's recent downturn in form gives them a fighting chance of enjoying their share of the spoils.
The defending champions have struggled of late, and only put an end to a seven-game winless run with victory over Nottingham Forest.
Despite this however, Butt warned that recent struggles will not make his former club's trip to the Etihad any easier.
He said: “I don't think in a derby, you can't really put a league position on the facts of us winning or not winning.
“I think it's just a one-off game. Anything can happen in derbies. It's passionate, it's emotional."
Although City won the league, United stopped them winning the FA Cup with another local boy, Kobbie Mainoo, scoring the winner to break rival hearts
6
Although City won the league, United stopped them winning the FA Cup with another local boy, Kobbie Mainoo, scoring the winner to break rival heartsCredit: Getty
Five memorable Manchester derbies for Nicky Butt
10 October, 1995 - 1-0 win on Manchester derby debut, playing entire match as Paul Scholes scores the winning goal in the Premier League
18 February, 1996 - United beat City 2-1 in FA Cup fifth round tie, and later go on to lift FA Cup
18 November, 2000 - Plays 90 minutes as the Red Devils claim a 1-0 win over their rivals in the first Manchester derby in four years
9 November, 2002 - City beat United 3-1 with Butt missing the match. This was the Citizens' first derby win since 1989
14 March, 2004 - Suffers first and only defeat derby defeat on the pitch as United are humiliated 4-1 at the Etihad
Butt continued: “What's happened over the last few years with derby games, particularly away from home, is Man United have sat back and counter-attacked, and City have struggled with the pace of [Marcus] Rashford and others.
Read More on talkSPORT
“So you just don't know what you're going to get out of a derby. They could come out all guns firing and win 5-0, or we could win 2-1 or 2-0.
“You just don't know, and I think that's the beauty of a derby.”