'It is the first time we've played City when they have the chance of actually achieving something'
He has been through 14 Manchester City managers and 38 derbies, but Alex Ferguson conceded that this might be the most important of them all.
Only in the early years of his reign when he wrestled with an underperforming, over-drinking side have the red and the blue halves of Manchester met as equals. However, should City make it into the Champions League, the United boss believes it could open a floodgate to the kind of spending that he could not and would not want to match.
"There is a definite emphasis on this derby game that has never been there before in my time here," he said. "It is the first time we have played City when they have a chance of actually achieving something. We always believe that we can get to Champions League finals, but for City just being in the competition would be the most exciting thing ever.
"The thing is City can buy. They have such an amazing amount of buying power. If they qualify for the Champions League, you can rest assured they will buy players. We have a reasonable structure in place. We may need to tweak the squad here and there but we like to buy young players who we can develop.
"We have signed Javier Hernandez from Mexico and we may sign two more at the most -- because that is the way we are. That is all we need. I don't think we will be in competition with Manchester City for players because they will be after different types of footballers."
Tottenham's first league victory in a north London derby for 11 years left Ferguson enthused, not just because it knocked Arsenal out of the title race, but because it showed "they are definitely capable of beating Chelsea" this evening.
However, that would be meaningless to the Scot without victory for United at Eastlands and, without their talismanic striker, United looked weary and disjointed at Blackburn last Sunday.
The risk of playing Wayne Rooney against Bayern Munich last week was justified by the way his presence galvanised United in the first half at Old Trafford -- although, unsurprisingly given the damage done to his ankle in the first leg, his touch was awry.
"With Wayne we have to be 100pc right because this derby will be different to the Bayern game in the sense that it will be really hectic, particularly in the early part," his manager said.
Against him will be Carlos Tevez, who remarked towards the end of his final season at Old Trafford that he, Cristiano Ronaldo and Rooney could together form the finest attack in world football. Now there is just Rooney left and Ferguson, typically, had no regrets about not taking up his agent's offer to buy Tevez for £25m -- despite the difference his 22 goals this season might have made.
"You cannot dispute he has had a great goalscoring season," Ferguson said. "I thought he had a good first season with us but in the second he didn't feature as much. He had far more competition with us than he has at City.
"I have no regrets at all about Tevez, none whatsoever. We tried to buy him but we didn't match the money they (his agents) wanted, therefore the boy moved on. There is no bitterness for me. Players leave here; some do well some don't."
It was on an April day in 1974, the year United were relegated, that Denis Law's back-heel for City rubbed salt into their wounds. It was on a similar spring afternoon that City handed out the blue-and-white scarves that Roberto Mancini has made his trademark.
Ferguson joked that for all the scarves displayed at what he used to call 'The Temple of Doom' at Eastlands, Stuart Pearce's side did not actually manage a shot on target. It was 2007; United won, Pearce was sacked and City have fired another two managers since.
"We need to win, not because it is the derby but because this is an important game," said the latest, Mancini. "This last month is fantastic for us because we are going to play perhaps the most important games in the club's history."
Those that saw City win the championship in 1968 at St James' Park on the final day of a season when United, their nearest rivals, stumbled at home to Sunderland might disagree. They finished second in 1977 and fourth a year later, too, although that did not seem to matter quite so much. It earned them a place in the Uefa Cup and a 3-0 win over Milan at Maine Road.
Under the circumstances, Mancini's pledge on succeeding Mark Hughes in December that he would qualify City for the Champions League in May and win the Premier League next season was a brave one. Just like the statement from Liverpool's incoming managing director, Christian Purslow, that he would make a club that now stands sixth in the table, "the biggest in the world", it can so easily be quoted back.
Mancini was asked what it was like to walk half the length of Old Trafford after Rooney's header in the closing seconds had dashed Wembley -- and the promise that the banner on the Stretford End that marks City's years without a trophy would come down.
"It was not a good feeling. We did not deserve to lose and before his (Rooney's) goal I thought that if we had extra-time we would win. I went to Ferguson's office afterwards and we talked about English football, and about wine. He was friendly." Of course he was, he had won. (© Daily Telegraph, London)
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