LEE Cook scored his first goal in 15 months when he rifled home a low left-foot drive with the almost the last kick of the first half - but it wasn't enough.
The winger was replaced in the second-half by Antonio German, and although no blame was attached to the youngster from Harlesden, it changed the nature of the game.
Derby equalised soon after Cook's departure when Shaun Barker cleverly made space for himself in the box to leave Carl Ikeme helpless in the Rs goal.
Rowan Vine got a rare chance to start a game in Hoops - and nearly lived up to expectation when he smashed a 20-yard shot aginst the bar in the dying minutes - but this was a game there for the taking long before that.
Derby had just enough time to restart after Cook's goal, but that was that for a 45 minutes in which Hoops ran the show - and could have been 2-0 up after 13 minutes had not been for Stephen Bywater in the Derby goal.
The Rams shot-stopper diverted a low hit from Jay Simpson around his post - and did even better when he parried a blaster from Matt Connolly over the bar a couple of minutes later.
But the rest of the half was as damp as the weather with the misty rain greasing up the surface.
The slick conditions almost gave lack-lustre Derby a leg-up when Peter Ramage connected with a clearance but only succeeded in connecting with Kaspars Gorkss' leg to send the ball whistling past his keeper - but mercifully past the post as well.
Rangers were not so lucky in the second 45 minutes, when apart from Vine finding the woodwork, the ref found his notebook to caution Alejandro Faurlin for a needless shirt tug.
Hogan Ephraim and Matt Hill were the other subs who couldn't get a second win for boss Neil Warnock since he took over at QPR - and just as worryingly - Matt Connolly went off with a problem as early as the 33rd minute