Colin Kazim-Richards’ 44th minute strike, combined with a quick-fire second-half double from Scott Dann and Jordan Rhodes ended the Rams’ hopes of an FA Cup Fifth Round tie.
Kazim-Richards was relentless in his charge towards goal when he opened the scoring at Pride Park, before Dann’s 66th minute volley – a contender for FA Cup goal of the round - doubled Michael Appleton side’s lead.
Five minutes later Rhodes raced clear inside the Rams’ penalty area before chipping the ball over Adam Legzdins
to complete the scoring, on an afternoon Rovers proved devastatingly clinical.
The Rovers’ line-up was littered with Premier League experience, and that quality was exemplified in the opening six minutes, when Norwegian international Morten Gamst Pederson’s beautifully flighted free-kick was inexplicably headed wide by Dann, from within the six-yard box.
However, with 10 minutes gone, Appleton was forced into making his first substitution of the game, as former Manchester United striker Joshua King struggled with injury, and was subsequently replaced by Ruben Rochina.
Other than Dann’s header, the Rams’ high pressing style of play restricted the Lancashire outfit to speculative crosses into the penalty area, and Derby’s tempo was almost rewarded when Jamie Ward found a pocket of space on the edge of the penalty area, but his half-volley was superbly blocked by Grant Hanley.
Like the earlier League encounter between the two sides at Pride Park this season, it was a tightly contested opening, with minimal clear-cut chances on show, although Pederson did force Legzdins into his first save of the game in the 26th minute, with a viciously struck free-kick.
Four minutes later the Rams had their first real sight of goal when Paul Coutts teed up Will Hughes 25-yards out, but the 17-year-old’s subsequent strike was blocked, before the ball span harmlessly into the arms of goalkeeper Jake Kean.
But unfortunately for the Rams, the first 45 minutes ended the same way as the League fixture in October, as Rovers took the lead on the stroke of half-time.
Richard Keogh was outmuscled by Kazim-Richards, who powered his way towards goal; the former Brighton and Hove Albion striker kept his composure and fired into the net, despite the best efforts of ‘keeper Legzdins.
The tight affair continued in the second half, with the Rams’ best opportunities in the first 15 minutes after the restart falling to Mark O’Brien and Ward.
Firstly O’Brien’s towering header from Ward’s in-swinging free-kick was well held by Kean, before Ward was denied by the former Rams’ shot-stopper as he looked to capitalise on the goalkeeper’s mistake.
But Appleton’s side continued to threaten and almost doubled their advantage through Markus Olsson when the lively winger volleyed the ball into the turf from 20-yards, but his strike was superbly clawed away by Legzdins.
However, Legzdins could do nothing about Danns’ strike moments later. Danny Murphy picked out the former Birmingham City defender with a pinpoint pass, and Dann brought the ball down on his chest 20-yards from goal, before rifling an unstoppable effort into the roof of the net.
The Rams’ misery was compounded in the 71st minute when Scotland international Rhodes latched onto Markus Olsson’s heavy touch to lift the ball over the onrushing Legzdins, and put Rovers into an unassailable lead.
Derby County: Legzdins; Brayford, Keogh, O'Brien (O’Connor 82), Roberts; Coutts, Hendrick, Hughes (Davies 74), Bryson; Ward (Jacobs 73), Sammon.
Subs Not Used: Fielding, Freeman, Bennett, Doyle.
Blackburn Rovers: Kean; Lowe, Dann, Hanley, M. Olsson; M. Olsson (Dunn 82), Pederson, Murphy; King (Rochina 10), Rhodes, Kazim-Richards.
Subs Not Used: Usai, Givet, Nunes, Gomes, Goodwille.
Attendance: 14,013 (1,287 visiting supporters).