Huddersfield boosted their survival hopes by coming from behind to earn a 1-1 draw and deny Derby a sixth consecutive home win.
In a game low on quality and played in driving rain for long periods, Derby looked on course for another Pride Park victory when Tom Lawrence smashed in a spectacular strike.
But the Terriers bit back nine minutes from time when Harry Toffolo punished a defensive error to run on and score, and it needed a fine save from Kelle Roos to deny Chris Willock a late winner.
Rain was falling heavily at kick-off with conditions set to get worse, and an early cross from Andre Wisdom almost caught Huddersfield out as it swerved in the wind.
Derby's next attack almost opened Huddersfield up as Chris Martin ran forward in the 10th minute and squared the ball, but it deflected off a defender with Martyn Waghorn about to shoot.
Huddersfield had a chance four minutes later when Fraizer Campbell spun 12 yards out but his low shot was too close to Roos.
Waghorn had a shot deflected behind before Wayne Rooney's 25-yard strike was easily held by Jonas Lossl, but Derby were forced into a change when they lost Duane Holmes in the 29th minute.
Lossl had to push away a Rooney free-kick as Derby continued to threaten, but Huddersfield had a great chance in the 39th minute when Junior Bacuna's corner found Campbell unmarked but he headed wide.
Derby forced Lossl into another save when he turned behind a Graeme Shinnie shot but the half ended with Danny Simpson's strike going just wide of Roos' right post.
The rain eased by the start of the second and Huddersfield started strongly, with Campbell thumping a drive from the edge of the box against the inside of a post with Roos beaten.
But Huddersfield were trailing in the 61st minute when Rooney took a short corner, Shinnie rolled it across and Lawrence smashed it into the top corner from 20 yards.
Derby almost doubled their advantage eight minutes later when Wisdom whipped the ball across but Waghorn's diving header was straight at Lossl.
Huddersfield were convinced they should have been awarded a penalty in the 73rd minute when Campbell looked to be clipped by Matt Clarke but referee Craig Pawson was unmoved.
Lawrence sent a volley wide from another Rooney corner but Huddersfield levelled in the 81st minute.
Jayden Bogle's poor header was seized on by Toffolo, who ran into the box and squeezed the ball between Roos and his near post.
Huddersfield had a chance to go ahead three minutes later when Willock was put through but Roos got a hand to his low shot.
What the managers said...
Derby's Phillip Cocu: "It was bad defending, it's never one mistake or bad judgement but the clearance with the header by Bogle, it was a very easy header but he gives it away. Then he doesn't push him to the outside or go to the inside, it's just basic, so for me it confirmed he was maybe upset he didn't play.
"But you have to put your ego aside and when your team-mates need you, you have to be 100 per cent focused in the game so it was obvious it was not good enough from his side. I don't think confidence is a problem with Jayden, he is a right full-back with a lot of potential going forward but he has to learn that if you are a defender, you have a big responsibility towards the team to defend."
Huddersfield's Danny Cowley: "He's [Toffolo] a really good kid, he's a down to earth honest, hard-working boy, he's got three kids, a lovely family and it's really nice when good things happen to good people. He's come to this level and it's a huge jump as everyone knows. This time last year he was playing in League Two and he's done really well. It was a great goal and he's going to be fine.
"Harry's improving all the time, he's playing with a real confidence and I always say to all the young players, the better they do the harder they have to work. It's one thing getting to the level, it's another mastering the level but he's improving by the day."