Birmingham were relegated from the Premier League last season but despite an encouraging start faded away badly as Nigel Clough's side showed the sort of spirit that was badly missing at the tail-end of their Championship campaign last season.
Losing start: Chris Hughton's Birmingham crashed to defeat at Pride Park
City opened the scoring through Curtis Davies but were pegged back by Rams' new signing Jason Shackell. Steve Davies completed the turnaround before the break.
The Birmingham centre-back hit a bullet header past Frank Fielding after 17 minutes, but Shackell's equalising effort with his head was just as impressive as he nodded home from a free-kick eight minutes later.
And with three minutes until the break, Derby sparked to life when Steve Davies whistled the winner past Boaz Myhill from 25 yards.
Hughton's side are bidding for a quick return to the top flight this season but have been weakened by a player exodus this summer which has seen the likes of Craig Gardner, Sebastian Larsson, Barry Ferguson, Roger Johnson and Ben Foster all leave.
Five of the visitors' starting XI were new faces with former Inverness striker Adam Rooney on his own up front.
Derby had plenty of new recruits involved too, among them Frankie Fielding, in goal, as well as Jamie Ward, Shackell, Kevin Kilbane and Craig Bryson.
The Rams had the first chance of the match when from a corner when Lee Croft half-volleyed over from close range in a packed penalty box.
MATCH FACTSDerby: Fielding, Brayford, Shackell, Anderson (O'Brien, 34), Kilbane, Bailey (Hendrick, 82), Croft, Bryson, Ben Davies, Ward (Robinson, 77), Steve Davies. Subs not used: Legzdins, Maguire.
Booked: Ward, Steve Davies, Ben Davies
Birmingham: Myhill, Carr, Davies, Caldwell, Ridgewell, Burke, Fahey (Wood, 58), Mutch, Gomis, Beausejour, Rooney. Subs not used: Doyle, Murphy, Dann, Redmond.
Referee: Neil Swarbrick (Lancashire)
But it was the side relegated from the Premier League that bossed the play as they proved the more efficient in possession.
Only a fine save from Fielding denied Jean Beausejour the chance to retake the lead for the visitors.
City were unlucky to be behind at thebreak and continued to dictate the play after half-time, with Stephen Carr causing the hosts plenty of problems on the right wing.
But it was Derby who had the first chance of the half and they should have doubled their lead.
Lee Croft's cross from the byline only required Jamie Ward to get a touch from two yards out, but the forward missed the ball completely as the chance went begging.
Clough's side grew in confidence as the second period went on and Ward again had a great chance to score only to be denied by the impressive Myhill.
Hughton made his first substitution just short of the hour mark, bringing on Chris Wood for Keith Fahey, with Jordon Mutch's effort on the edge of the box going wide for the visitors moments later.
City side started to come back into the game and after Chris Burke's effort crashed off the post, Carr missed the rebound from six yards to blow a fantastic chance of grabbingthe equaliser.
With 20 minutes remaining Birmingham were denied another opportunity to level after sub Woods was put through on goal, but foiled by the advancing Fielding
Derby were hanging on near the end, with Davies again rising up for a header but this time nodding wide from close range with four minutes left.
But the Rams managed to weather the Birmingham storm and controlled the final few minutes to kill off the game and grab a deserved hard earned win.
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