The two sides went into the break all square at 0-0 after a tight first half, but Ross McCormack finally broke the deadlock with a fine curling effort in the 66th minute.
The hosts' lead lasted less than six minutes, however, as Derby were awarded a penalty shortly afterwards. Connor Sammon's spot kick came back off the foot of the post, but Paul Coutts was on hand to bundle in the rebound.
The winner came with just three minutes left to play when Ben Davies's corner was glanced in by Jake Buxton at the near post.
Here, Sports Mole takes an in-depth look at another disappointing defeat for Leeds.
On target 3
On target 7
Was the result fair?
A draw would have been the fairest result in this game. The first half lacked quality all round and was a very even affair with. Leeds struck the bar in the only moment of note, but the two sides deserved to be level at the break. The second half was a much more exciting spectacle, but again it was quite even throughout. Derby had begun to exert quite a bit of pressure on Leeds just before the winner so, on that basis, if anyone deserved to win it was the Rams, but a share of the spoils would have been a more just outcome.
They were greeted with boos at the full-time whistle and there is a feeling of discontent around the club at the moment. This shone through in their display at times this afternoon, especially in the first half during which they were poor. They were significantly better in the second half and can count themselves as unlucky to have come away with nothing, but their performance did nothing to alleviate the worries some fans have. They will need to improve if they want to avoid getting dragged into a relegation battle.
Derby's performance was pretty similar to Leeds's. Both sides had spells in the match when they were on top and certainly Derby were in the ascendancy when they scored the winner, but they were still short of their best. They also had a very poor first half before improving in the second. Still, they were the away team and did exactly what they had to do to come away with all three points, so while it may not have been the best performance, Nigel Clough won't mind.
Sports Mole's man of the match
Richard Keogh: The defences were on top for large periods of this match, and Keogh was a towering presence at the back for Derby. He put in one tackle of the highest order in the first half and continually got the better of Connor Sammon.
This one has to go to referee Roger East. In the 85th minute, with the score still at 1-1, Michael Jacobs went down theatrically inside the penalty area so the referee had to decide whether to award a spot kick or call it a dive. Eventually, he opted to give Derby a free kick just outside the box despite the foul clearly being committed inside the area. His blushes were spared slightly by Derby's winner shortly afterwards, but it was still a strange decision from the referee. Sammon also deserves a mention in this category for his missed penalty.
Roger East had a mixed game. The gaffe mentioned above was a low point for him, but he dealt with a tricky match quite well on the whole. He was very busy in the first half especially as it was very scrappy, but he did well to resist the temptation to bring a card out on a number of occasions. He did miss one clear penalty, but got the one he did award right.
Leeds: Leeds will be looking to win for the first time in seven matches when they take on Charlton Athletic at the Valley on Saturday.
Derby: Derby, meanwhile, will look to continue their late push for promotion at home to Ipswich Town, also on Saturday.