In as little as 18 months, Simon Grayson's side could be mixing it with the likes United, Arsenal, Chelsea and Liverpool on a regular basis, in the Premier League.
Back in the big time: Jermaine Beckford's extraordinary FA Cup third round winner for Leeds at Old Trafford put the spotlight back on the League One leaders
A 1-0 defeat at the hands of Chelsea in May 2004 was the Yorkshire club's last match in the Premier League and in 2007 the club dropped into the third tier of English football - for the first time in their history.
But defeating Sir Alex Ferguson's side has given the players and fans belief that they can return to where they belong, and mirror the returns to glory these clubs enjoyed.
Manchester City When it comes to football, things aren't always rosy in Manchester. Financial strife and a flurry of managers was the backdrop to City's dive down the leagues in the mid-90s.
Their departure from the Premier League in 1996 was compounded by a drop into the third tier for the first time in their history the following season.
Now and then: City now dream of Champions League football but it was different story in 1999 when they overcame Gillingham to win promotion from Division Two
But redemption wasn't too far away as the club clawed its way back up to the top-flight, only to get relegated back into the Championship.
Still, this was all sent to test the long suffering City fans who have been enjoying the delights of playing in the big league since 2002 and are now, if you haven't heard, the richest club in the world.
FulhamThe club are flying under the stewardship of Roy Hodgson and it's remarkable to remember Fulham were playing in the fourth tier of English football only 13 years ago.
Now and then: Fulham are flying high in the Premier League and in Europe, only years after Barry Hayles (below) and co helped the club rise through the leagues
Mohamed Al-Fayed's west-London revolution pre-dated Chelsea's by five years and, within four years of buying the club, they were making their Premier League bow.
The club have dallied with relegation on several occasions since entering the top-flight but Hodgson has steadied the ship and the propects look good for the Cottagers.
Stoke 1985 will forever be remembered as bad year for Stoke City fans - the club was relegated from the top-flight after a season that saw them win just 17 points and enjoy three wins.
Now and then: Stoke City are now in their second Premier League term following a 23-year exile from the top-flight when they were relegated from it in 1985
This relegation was the pre-cursor to a period in the football wilderness, including three seasons in the third tier between 1990 and 1993, ended in May 2008 with promotion back to the Premier League.
BirminghamBlues fans only have to think back to the early 90s to remember their team playing third tier football - and what a contrast to the current fortunes for the club.
David Sullivan arrived the at St Andrews with the club at it's lowest ebb, buying Birmingham City for a reported £700,000 and only left recently after Carson Yeung's buy-out with the club in great shape.
Now and then: After many years yo-yoing between the divisions, Birmingham are hitting the heights in the Premier League this season under boss Alex McLeish
After a couple of years yo-yoing between the Premier League and Championship, the Blues are now unbeaten in their last 11 league games, a feat the club has never achieved before in the top flight and are sitting just outside the Champions League places.
Alex McLeish's side look set to remain in the Premier League for some time to come.
BurnleyEnglish league champions in 1960, the Clarets dropped out of the top flight in 1976 and almost out of league football completely when they were in the basement league in 1987 - it was a dramatic decline of fortunes for what was one of the game's greatest clubs.
Now and then: Burnley's dramatic return to the top flight is a far cry from the days when they were in the lower leagues facing the likes of the old-Wimbledon FC
A steady rise through the leagues for the two times league champions culminated in Burnley's return to the Premier League via the play-offs last May.
Owen Coyle's side celebrated their return to the big time in style with a 1-0 victory over North-West rivals Manchester United in their first home game in August.
.and those waiting in the wings to start their bounce-back.NorwichNorwich graced us with their presence for much of the 80s and some of the 90s but have managed just the one season in the top-fight this century. They're going well in League One at the moment so come on, 'let's be 'avin you' back in the top flight.
Let's be 'avin you: Norwich are enjoying fine form in League One this term
Charlton A spectacular drop down the leagues began after the departure of long-term boss Alan Curbishley but they are enjoying a good season so far in league and a return to the Premier League isn't out of the question.
Notts Countywe're waiting for the Sven-Goran Eriksson-inspired charge back up the leagues to start but with the financial situation a little cloudy at Meadow Lane, we may have to wait for their return.
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