Yohan Benalouane's goal came after just 74 seconds
Nottingham Forest moved to within three points of the Championship play-off spots and within a point of Derby County as Yohan Benalouane's second-minute goal settled an intriguing East Midlands derby.
Benalouane reacted smartly from close range after the Rams failed to deal with a Joe Lolley free-kick and the 74-second opener set the tone for an unusually open, but typically frenetic local contest in front of a sell-out City Ground.
Martyn Waghorn wasted a glorious opportunity to level when one-on-one as Derby controlled possession and probed for openings.
Forest, with Lolley and Ryan Yates outstanding in midfield, remained a constant threat on the counter-attack but did not need the comfort of a second goal as they closed out their first win over their fiercest rivals in seven attempts.
A second consecutive defeat for Frank Lampard's Derby leaves them seventh, just one place ahead of Forest, who climb to eighth.
The Rams had plenty of the ball and got in numerous good areas in the final third but only managed six attempts on goal.
Forest were buoyed by the early goal when Benalouane reacted superbly to turn in Daryl Murphy's header after Jayden Bogle's defensive header went high into the air.
The home side were happy to surrender possession and, Waghorn's poor dinked finish aside, the tactics worked and they created the better chances.
Lolley's fierce strike was almost turned in by Yates and, after the break, Murphy was a fraction off target a with a low shot across goal.
The Rams, who have now lost three times in a four-game winless away league run, continued to see more of the ball, but Forest stood firm.
O'Neill nous prevails over Lampard
Derby's preference for possession football using Tom Huddlestone as the fulcrum alongside Andy King made for a fascinating first-half contrast against a Forest side who went for the high-tempo approach and looked to exploit some ageing, albeit very wily, legs in midfield.
Huddlestone's slick passing and ability to see and execute a pass, short or long helped create several promising situations before the interval.
But the Reds, with Lolley, Yates and Jack Colback all prominent as they snapped into tackles, brought a constant menace and the greater goal threat on the break.
Huddlestone's withdrawal brought more urgency as the match became increasingly fiery and more derby-like.
A sixth red card in eight meetings between the sides looked likely but Forest remained in control of their emotions to earn victory.
January signing Yohan Benalouane's goal was his first for Nottingham Forest - on only the 31-year-old Tunisian international's sixth appearance
