Manchester City made it three Premier League wins out of three this season with a shock win over rivals United.
Geovanni celebrates after putting Man City ahead
United dominated the derby from the off and Nani forced Kasper Schmeichel into two good saves as City hung on.
The home side had created nothing until they took the lead when Geovanni's shot deflected home off Nemanja Vidic.
Vidic hit the bar and Carlos Tevez saw a late header fly wide but City, led by the impressive Micah Richards, held out and United are still winless this term.
Sir Alex Ferguson's side have taken only two points from their first three league games and the champions lie seven points behind City, who are at the summit of the table.
It has been a perfect start for the Blues and their new boss Sven-Goran Eriksson, who is yet to see his hastily-assembled side concede a goal.
That statistic seemed unlikely early on as United started like a train and, with City struggling to keep the ball let alone create anything with it, it seemed only a matter of time before they took the lead.
Inside the first five minutes Nani forced an instinctive block out of Schmeichel and the young keeper did well to hold a firm shot from the same player soon afterwards.
United had set up camp inside City's half by now and another neat move set Patrice Evra running clear - only for him to slice his shot horribly wide.
City, who had lost Valeri Bojinov to injury early on too, were simply hanging on and if it had not been for the brilliant Richards they would surely have collapsed.
England coach Steve McClaren is short of centre-backs for Wednesday's friendly with Germany and he will surely be glad he can call on the 19-year-old City defender to play there, if needed.
Richards was again in imperious form at the back for City
Richards, nominally a right-back, began the season in the centre under Eriksson and has emerged as a real star of the new City regime.
He made one brilliant tackle to deny Tevez as the Argentine closed in on goal and then made a timely clearance after Schmeichel had dropped a Ryan Giggs cross.
But at the other end, City were still creating absolutely nothing and it was a total shock when they took the lead in the 31st minute.
With United's defence backing off, Elano fed Geovanni, who let fly with a 25-yard shot that spun off Vidic's back and swerved into the corner of the net.
If anything, City controlled the remainder of the half but United were soon threatening again after the break.
Vidic beat Richard Dunne to Giggs' corner but saw his header cannon off the crossbar before another dangerous Giggs cross was somehow cleared from danger by Richards.
Yet more United possession followed and Tevez went close to levelling when he flicked another Giggs ball agonisingly wide.
But the goal would just not come for Ferguson's men and their frustrating afternoon was summed up in injury time.
Another Giggs corner found its way to Tevez at the far post but the striker could not react quickly enough to find the target with his header and City survived again.
Man City: Schmeichel, Garrido, Richards, Dunne, Corluka,
Geovanni (Ball 74), Hamann, Johnson, Petrov,
Bojinov (Mpenza 8), Elano (Bianchi 63).
Subs Not Used: Hart, Onuoha.
Booked: Hamann, Corluka.
Goals: Geovanni 31.
Man Utd: Van der Sar, Brown (O'Shea 73), Ferdinand, Vidic,
Evra, Hargreaves, Scholes, Carrick (Campbell 73), Giggs,
Nani (Eagles 60), Tevez.
Subs Not Used: Kuszczak, Silvestre.
Booked: Brown, Ferdinand.
Ref: Mark Clattenburg (Co Durham).