Callum Paterson scored a scrappy second-half goal to edge a tight game between two sides battling at the wrong end of the table.
Derby had lost just once in eight matches with Wayne Rooney as interim manager, but they are now separated from the drop zone only by goal difference.
Story of the match
The game started in a fashion befitting of the Championship’s two lowest-scoring teams this season, but Derby soon began to offer the kind of threat that had earned them a 4-0 win at Birmingham City three days previously.
Matt Clarke headed the first shot wide at the near post before Graeme Shinnie was handed a far better chance. Possession was recycled after Joe Wildsmith parried Louie Sibley’s swerving effort from distance, and midfielder Shinnie was teed up perfectly only to aim his shot wide of the target.
Sheffield Wednesday’s threat was fleeting in the opening stages, their first effort lofted over the bar by Adam Reach after he came inside and in between the central defenders to receive Kadeem Harris’ pass.
Otherwise, it was all Derby attack. Clarke was denied by a flying Tom Lees block following Sibley’s knock down, and from the resulting corner Wildsmith denied Krystian Bielik’s header from close range before the assistance of his defenders helped win the ensuing scramble.
They were getting closer and closer, and couldn’t have been more unfortunate when Craig Forsyth’s brilliant cross was headed by a stretching Colin Kazim-Richards onto the crossbar.
Wednesday began to make an impression on the first half only towards its conclusion, culminating in a glorious stoppage-time chance as Elias Kachunga, brought on for the injured Josh Windass, headed Barry Bannan’s free-kick wide.
Derby looked a danger again at the beginning of the second half. Nathan Byrne beat four defenders with a mesmerising run only for his own heel to stop him, though the visitors retained the ball and Forsyth found Sibley who turned only to fire wide.
Substitute Kachunga was presented with a second big opportunity for Wednesday, but his tame header didn’t trouble David Marshall after a long throw travelled all the way through to him. At the other end, a wicked Forsyth delivery somehow evaded everyone with Sibley and Kazim-Richards close to tapping in.
The first goal was always going to be crucial and after so many near-misses, it was the home side who got it. Of all things, it came from a headed scramble in the box, as a game of head tennis was finished by Tom Lees' nod towards goal and Paterson’s flick beyond Marshall from close range.
Derby were almost literally handed a leveller when Wildsmith, deputising for Keiren Westwood between the posts, spilled a Shinnie punt from the edge of the box and had to scramble to stop it creeping across his own line.
But Rooney’s men struggled to fashion many chances of their own as the clock ran down, the best coming deep in added time when Liam Shaw’s poor clearance fell to Lee Buchanan only for Harris to fly in and save the day with a match-winning block.
Owls can be positive
Under both Garry Monk and Pulis, particularly the latter, Sheffield Wednesday were a cautious and overwhelming functional team.
Many have suggested that the squad has now been built in such a way that getting them to be anything else will be an impossible task, at least in the short term. But the two performances under Thompson this week suggest that they could be much more.
Granted, this was still no spectacular display. They were under pressure for much of the first half, and after scoring the goal were happy to sit deep and frustrate to the final whistle.
But with the change of system to 4-4-2 freeing both Harris and Reach to be threats, as well as providing a second man up front, they look a different side, and whoever takes charge of the club next has something to build on if they want to go down that path.
Rooney’s goal-shy Rams
Despite Rooney’s prolific playing career, his Derby side have struggled for goals during his reign as interim boss, scoring nine goals in as many matches
Although their goal-a-game rate is better than under Philip Cocu at the beginning of the season, their total of 14 goals is the lowest of any side in the Championship this season.
It looked like things might have clicked into gear on Tuesday night when they enjoyed a sensational win at Birmingham, but a fourth blank of his tenure here means that result remains an outlier.
Derby were so good for most of the first half, and Rooney suggested after the match that his side had “got a bit bored of doing the right things, found the game maybe a bit too easy at times”.
There’s no doubt they have the quality at their disposal and they look a genuinely threatening team now, but some simplification – and composure – would be most helpful.
Man of the match: Tom Lees (Sheffield Wednesday)
With Chey Dunkley the latest defender to be ruled out through injury, Lees stood up and provided great leadership at the back for Wednesday alongside teenage partner Shaw.