Sheffield Wednesday ended a poor run of form as they beat Sheffield United to stay in touch with their city rivals near the top of League One.
Chris O'Grady grabbed his seventh goal of the season when he headed in Lewis Buxton's cross.
Earlier, Lee Williamson hit the bar with a free-kick as United created several openings.
Victory ended a run of four defeats for Wednesday, who are now two points behind second-placed United.
Owls boss Gary Megson, who highlighted Wednesday's lack of goals in the build-up to what was a fiercely-contested encounter, will be delighted with a victory that lifted them above Huddersfield and Milton Keynes Dons into third place, especially as his position has come under threat.
United, on the other hand, will have to lick their wounds after this setback. They remain 10 points behind League One leaders Charlton as manager Danny Wilson completed a disappointing return to his former club.
Megson will also have been pleased by the contribution of new loan signing Michail Antonio, who looked a welcome addition to their supply line.
His cross was narrowly missed by Ryan Lowe, with Reda Johnson heading over from an early corner, but United posed more questions in open play in a white-hot first half.
Leading scorer Ched Evans was a constant threat and he linked well with Williamson, with the winger inches away from opening the scoring when his free-kick crashed against the bar before thudding down close to the line.
Evans twice went close either side of that chance as United finished the opening period on top, but Wednesday improved after the break and the majority of a 36,364-strong crowd found their voice when O'Grady was narrowly off target from 25 yards.
Megson then brought on Gary Madine as the Owls began to force the game, and the manager got his reward on 73 minutes when Buxton made an overlapping run to cross for O'Grady to nod in from 10 yards.
United responded with a flurry of changes but goalkeeper Stephen Bywater saved Will Hoskins's late header after stopping Ryan Flynn's effort.
But they could not breach the Wednesday goal and, although it marked only their third game in 13 where they had not won, they now have to regroup and deal with their arch-rivals once again breathing down their necks.
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Sheffield Wednesday manager Gary Megson told BBC Radio Sheffield:
"I'm proud all the time being manager of Sheffield Wednesday, but I suppose that's intensified given the fact that we've just won a game against our local neighbours and it's a great feeling.
"I think it was always going to be a scrappy game, being a derby game and invariably they are settled by a mistake, a set-piece or a really, really top drawer goal and that's what it was.
"I couldn't see it coming from anyone, but ourselves, especially in the second half. It was near enough one-way traffic.
"They had one header late on, but really it was a loopy thing and Stephen [Bywater] chose to put it over the top, but as I say it was all one-way traffic."
Sheffield United manager Danny Wilson told BBC Radio Sheffield:
"It was a very tough game as we expected, there's nothing between the two teams.
"They've had a chance where they've created a little bit of an opening down the side of us, the only time in the game and they've taken their chance, which is disappointing from our perspective.
"We've had a couple of good situations today that we could possibly have done better. But we've been unlucky as well with the free-kick in the first half that's struck the underside of the bar and whether it's crossed the line or not. I'm not too sure, because I haven't seen it.
"It was nip and tuck all the way, we said before that there had been nothing between the two teams. They're good sides and two teams you expect to be challenging at the end of the season."
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