Even the normally ice-cool Swede allowed himself an extra smile of satisfaction at the result of a perfect smash-and-grab raid which maintained City's 100% start.

Brazilian import Geovanni was the Blues' matchwinner, his rasping 31st-minute effort flying in off Nemanja Vidic.

But City's real hero was teenage England defender Micah Richards, who barely put a foot wrong, producing a string of fine tackles and interceptions which emphasised just why he is regarded as the number one young player in the country.

So, while Eriksson marches to Arsenal next week having enjoyed a dream start to life as a Premier League manager, his old foe Ferguson can only reflect on a potentially ruinous opening to United's title defence.

As United head into the third weekend, only pointless Bolton and ailing Midlands trio Aston Villa, Birmingham and Derby are currently below them in the table and with the Red Devils not due back on stage until late on Sunday, they could be in a very embarrassing position by the time they kick-off against Tottenham at Old Trafford.

No-one at United will publicly admit it but with two points from three games, they are already so seriously adrift of the league leadership, it could be terminal.

There was no evidence of United's poor start having any effect on their confidence in the opening stages as they proceeded to tear City apart.

With Owen Hargreaves back after injury and anchoring the visitors' midfield, Paul Scholes and Michael Carrick were given licence to roam and the amount of space they found was almost embarrassing.

Nani twice tested the reflexes of Kasper Schmeichel, initially with a rasping near-post effort the young Dane - son of United legend Peter - kept out with his legs, then with a first-time shot after Scholes back-flicked a pass into his path.

Carlos Tevez was a constant threat as well, with Richards requiring all his lauded speed and agility to get City out of trouble.

Twice Richards brushed Tevez aside in a one-on-one foot race for possession and it was his tackle which launched the move which eventually saw City seize the initiative.

Richards is a certainly to feature for England against Germany on Wednesday, probably at right-back rather than the central defensive berth where he excelled here, and the teenager's cameo including a rushed clearance as Scholes closed in on the loose ball Schmeichel inexplicably spilled on the edge of his six-yard box.

In the entire first 45 minutes there was virtually nothing to worry Ferguson as he looked to emphasise his managerial superiority over a man with whom he clashed so often during Eriksson's five-and-a-half years with England.

But, as the veteran Scot is only too aware, a failure to make superiority count can prove very costly indeed.

And his heart must have sank as his defenders stood off Geovanni when the Brazilian collected a short pass from fellow countryman Elano 30 yards out.

Vidic made a belated attempt to close the midfielder down but turned his back on the shot, which flicked off his legs and flew past Edwin van der Sar.

Cue bedlam as the City faithful, who watched United effectively seal their ninth Premier League title on their previous visit in May, launched an extended bout of celebrations which threatened to submerge the visitors on its own.

If anything, Richards' first-half efforts threatened to be eclipsed by what he produced in the second.

As Giggs drilled in a low cross from the left, either Scholes or Tevez seemed certain to score, yet the teenager somehow muscled his way between them and cleared magnificently.

Scholes, visibly unhappy with Nani's erratic contribution, failed to take a couple of chances, then Tevez flicked Giggs' low cross agonisingly wide of the far post.

It was turning into the most one-sided defeat imaginable, with City pressed almost exclusively into their own half, Chris Eagles' introduction for Nani only increasing United's attacking momentum.

Ferguson's final gamble 17 minutes from time saw him hand Huddersfield-born striker Fraizer Campbell his debut. It didn't work.

There was just one last chance at salvation as John O'Shea swung over an injury-time corner. A yard out, on his own at the far post, Tevez seemed destined to score.

Ferguson was already celebrating when the striker's header went wide. It was that type of afternoon for United.

Micah Richards told Sky Sports News: "We're just delighted, it was a great team performance. We've come out and shown the fans we can do it. We can beat anyone."

He admitted expectations were raised now among City fans but said: "We've got the players to do it so why not?"

Kaspar Schmeichel was constantly under threat in the City goal to keep up the Schmeichel's proud family history - along with father Peter - of never being beaten in derby games.

He said: "I'm just taking every game as it comes.

"I'm lucky the gaffer has given me a chance and hopefully I can keep working as hard as I can.

"It was a massive team effort with luck once or twice but you need that."

Ferguson insisted United only had themselves to blame after squandering a hatful of chances against City.

"We had enough chances and played fantastic football at times," he said.

"We were just wasteful, we had so many opportunities to win it ourselves.

"I can't fault the performance - we completely dominated. But we should have sewn the game up.

"Of course you miss strikers but the number of chances we had and the amount of possession we should have won the game."

It means United have only got two points from their opening three games and Ferguson admits it will be very difficult to come back.

"We've got ourselves an uphill battle.

"We need to get a win under our belts."

Opposite number Eriksson admitted City rode their luck and moved to play down expectation at Eastlands.

"It's fantastic, it was a very difficult game and we were lucky as well.

"For possession of the ball and shots on target we'd have lost but the goal was what counted.

"Sometimes I wish we could keep the ball better but we won the game and three wins is very good.

"I think they (United) have been unlucky (at times this season) - they create so many chances but the season is very long and they will come back."

The former England boss also dampened any expectation of a tilt at the league title by the Blues.

"I don't think anyone expects that," he told Sky Sports News. "It's good to have a good start when you have so many new players and the confidence gets higher and higher."

The Swede admitted he was hoping to bring in more new signings, saying: "I hope we can take in one or two others but we have to do it quickly or it's too late."