To me, Liverpool will always be the derby game, just because of the history. When I came down here, they were the kingpins of England. My aim was to try and turn that round. It’s hard for me to go against history.Sir Alex Ferguson
You've got the two most successful clubs in the country and the rivalry is huge because of how close the clubs are and all the battles we've had over the years. If you ask any fan or player to pick a game they'd like to win, you look for United.Steven Gerrard
There are those who argue that the M62 rivalry isn't technically a derby game. But try telling that to anyone who has had any part to play in what is one of the most historically significant fixtures on the football calendar, and you will be laughed out of the building.
The two clubs might not share a city - 31 miles separates Anfield from Old Trafford - but what they do share is enough to resoundingly squash any pretences as to the famous feud's legitimacy. Two north-western cities with roots deep in trade, broadly similar in size and population, with footballing dynasties comparable to the extent that they are impossible to definitively split.
For all their footballing and cultural similarities, however, there are plenty on each side of the divide who would argue there is a chasm in every respect.
Both clubs have grown from working class foundations, yet classism has been a fixture since day one. When Liverpool FC were formed in 1892, Scousers were looked upon by those in Manchester with disdain; the city's new-found wealth through affluent merchants and mill owners conflicted directly with the dockers of Manchester, who made their money by getting their hands dirty.
Yet, 90 years later, when Liverpool was hit with a Thatcher-era unemployment crisis, 'lazy scousers' became a common jibe among those of a United persuasion, while “sign on, sign on, and you'll never get a job” became a fixture of the terrace repertoire whenever the two sides met in the 1980s.
The tables had turned, just as they have on the pitch on countless occasions. There were signs of that even in the rivalry's early years, when Liverpool earned promotion to the First Division in their first ever season, relegating Newton Heath in the process.
By 1906, they had won their second top flight title, in the same season Heath - now going by Manchester United - won promotion back to the top flight. By 1911, the two clubs were tied on two titles apiece.
Considering the renown the derby has gained over its far-reaching history, it seems almost impossible to consider that there was only ever one four-year period in which their dominance was split. Liverpool vs Manchester United has virtually always been defined by one side playing cat and the other mouse, often for decades at a time.
But for a brief spell the mid-1960s - when Matt Busby took on Bill Shankly in a real clash of English football's titans - the honours were even.
Both managers had been forced to rebuild their respective teams in the early part of the decade. Shankly had the Reds back in the big-time after eight seasons outside of the First Division, and his squad - led from the front by Roger Hunt and Ian St John - looked poised to return to former glories.
Busby, meanwhile, was faced with the far more solemn task of putting his team back together after the Munich Air Disaster in 1958. Among its 23 casualties, it took the lives of eight players who had won the 1957 title.
But by 1964, galvanised by tragedy, they were ready to go again, and took on their famous rivals in a famous four-season power struggle. Shankly's Reds struck first, Hunt's 33 goals edging United out by four points to win the 1964 title. United, however, hit back immediately, and the title changed hands between the two every year until the legendary Joe Mercer's Manchester City broke the cycle in 1969.
While there was a growing, volatile bitterness between the fanbases, however, Shankly and Busby remained great friends throughout - perhaps summing up the professional respect that still exists somewhere beneath the cloud of resentment.
You might not catch Jurgen Klopp speaking effusively about Ole Gunnar Solskjaer nowadays, but after Busby's retirement in 1969, Shankly admitted that the United boss was the greatest ever. He didn't mince his words either.
"Matt Busby is without the doubt the greatest manager that ever lived," Shankly said in 1970 (as per MEN). "I am not saying I think he is the greatest manager, I am saying he is the greatest manager. Facts can prove that."
So great was Busby's influence that it took United four permanent managers, and almost 20 years, to recover. They fell to pieces throughout the 70s and 80s - and were even relegated from the top flight in 1974 - while Liverpool went off.
Whether it was under Shankly, Bob Paisley, Joe Fagan and Kenny Dalglish, the Anfield giants did not stop winning while United faltered. 11 league titles and four European Cups came as their rivals desperately struggled, though United did pop up with the odd reminder that it wasn't all one way - famously causing an FA Cup upset as a James Greenhoff strike sank the Reds in the 1977 final.
No good thing lasts forever, however. And from a United perspective, it took the rivalry of a bolshy new Scottish manager to shift the balance of power.
When Alex Ferguson arrived from Aberdeen, with the goal of "knocking Liverpool right off their f***ing perch" you got the impression something was about to change.
Between 1972 and 1990, Liverpool won 11 league titles to United's zero. Between 1991 and the 2019, that score sat at 13-0 in the other direction.
Nowadays, we sit on the verge of yet another twist in the tale. With Fergie no longer in town, Jurgen Klopp has already achieved what Rafa Benitez and Gerard Houllier - for all their European glories - could not, and what Brendan Rodgers came so painfully close to doing before one of the most painful collapses in the club's history.
Is there a superior side in this rivalry? Both sides will say so, and have evidence in their favour. United, with a 20-19 lead in the league titles, argue their neighbours can't hold a candle to their greatness, while the Merseysiders' six European cups to their rivals' three is a major point of pride.
Presently, it's Liverpool - the reigning Premier League champions at the time of writing - who have the edge, though the pendulum is ready and waiting to swing back United's way.
But it says so much about this famous old derby that it might once again look one-sided - for the time being at least - but is still yet to lose its edge for a moment of its 129-year history.
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