Match ends, Sheffield Wednesday 1, Derby County 0.
Sheffield Wednesday spoiled Derby boss Wayne Rooney's run of one defeat in nine games as Owls stand-in boss Neil Thompson won the battle of the two caretakers at Hillsborough.
Callum Paterson's scrambled 61st-minute winner proved enough to hand the Rams their second defeat since Christmas.
That made it two wins from two for Thompson since he took over following the sacking of Tony Pulis on Monday.
Having begun the season with a 12-point deduction for breaking EFL spending rules, which was halved on appeal in November, Wednesday's sixth win of the season lifts them above Derby and out of the bottom three of the Championship for the first time, up to 20th.
Three of those six league victories have come in a four-game unbeaten run, the Owls having picked up four points from the final two games with Pulis in charge.
Substitute Jordan Rhodes was just stripping off to ready to come on and replace Paterson when the winning goal went in.
Derby failed to clear Barry Bannan's free-kick and, in the resulting scramble, Paterson nodded in for his fourth goal of the season - and second in as many games. And Rhodes had to wait another 11 minutes before that switch was eventually made.
The Rams had more of the possession and the better chances over the 90 minutes, going closest when Colin Kazim-Richards hit the bar in the first half.
The Owls improved after the break and visibly grew in confidence after going ahead.
But Derby were left aggrieved after being denied by referee Matt Donohue for a late penalty, for a blatant handball against Kadeem Harris - a decision that would little doubt have been overturned by the video assistant referee had this been a Premier League game.
This was Derby's fourth defeat since Philip Cocu's departure in mid-November, but only their second in nine games since Rooney took sole responsibility, after losing their first two matches in the immediate wake of Cocu's sacking.
The other defeat in Rooney's nine-game run of sole command came on Boxing Day at home to Preston, making this the Rams' second Christmas setback in three games, either side of a remarkable 4-0 win at Birmingham.
Owls caretaker boss Neil Thompson told BBC Radio Sheffield:
"We weren't at it first half. That was pretty obvious. The lads looked a bit leggy from all the games we've had over this four- or five-week period. And we rode our luck.
"But we had a word with one or two at half-time and we got a reaction. They were more positive, dug in and gave it everything they've got.
"Callum put his head in where it hurts and gave us something to hang on to. Six points gives us something to go forward into the new year."
Rams caretaker boss Wayne Rooney told BBC Radio Derby:
"It's clear that it was a penalty. The fourth official has clearly seen it's a penalty.
"I'm asking why there's no communication between the fourth official and the referee.
"The referee can't see everything. I get that. But it's disappointing that they didn't give it."
- 7K Harris
- 5PatersonSubstituted forRhodesat 72'minutes
- 18WindassSubstituted forKachungaat 37'minutes
- 3ForsythSubstituted forBuchananat 72'minutes
- 4ShinnieSubstituted forBirdat 72'minutes
- 7JozwiakBooked at 90mins
- 13Kazim-RichardsBooked at 90mins
- 17SibleySubstituted forHector-Ingramat 79'minutes
- 6te Wierik
- Matt Donohue
- Shots on Target
Second Half ends, Sheffield Wednesday 1, Derby County 0.
Kamil Jozwiak (Derby County) is shown the yellow card.
Corner, Derby County. Conceded by Kadeem Harris.
Attempt blocked. Max Bird (Derby County) left footed shot from the centre of the box is blocked.
Attempt missed. Max Bird (Derby County) header from the centre of the box misses to the left. Assisted by Jason Knight with a cross.
Colin Kazim-Richards (Derby County) is shown the yellow card for a bad foul.
Foul by Colin Kazim-Richards (Derby County).
Adam Reach (Sheffield Wednesday) wins a free kick in the defensive half.
Lee Buchanan (Derby County) wins a free kick in the defensive half.
Foul by Kadeem Harris (Sheffield Wednesday).
Offside, Derby County. Max Bird tries a through ball, but Jahmal Hector-Ingram is caught offside.
Offside, Sheffield Wednesday. Adam Reach tries a through ball, but Jordan Rhodes is caught offside.
Corner, Derby County. Conceded by Moses Odubajo.
Foul by Kamil Jozwiak (Derby County).
Liam Palmer (Sheffield Wednesday) wins a free kick in the defensive half.
Substitution, Derby County. Jahmal Hector-Ingram replaces Louie Sibley.
Foul by Jason Knight (Derby County).
Elias Kachunga (Sheffield Wednesday) wins a free kick in the defensive half.
Foul by Matthew Clarke (Derby County).
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