Jamal Lowe’s last-gasp goal saw Sheffield Wednesday come from behind to stun Derby 2-1 at Pride Park.
Danny Rohl’s side were second-best for long periods, falling behind when Ebou Adams fired the Rams in front early on.
But after Barry Bannan’s memorable finish had dragged Wednesday level, substitute Lowe pounced in the fourth minute of stoppage time from close range to snatch the points.
For the hosts, manager Paul Warne, who had seen Jerry Yates spurn a glorious chance shortly before Bannan levelled, it was a case of what might have been.
Derby started brightly, with Owls skipper Bannan conceding possession in midfield and allowing Nathaniel Mendez-Laing to whip a dangerous cross into the box.
Adams headed clear a thunderous effort from Marvin Johnson but recovered quickly to fire Derby into a ninth-minute lead. Marcus Harness beat his marker and produced a pinpoint centre which Adams powered home.
The Rams spurned an opportunity to double their advantage when Craig Forsyth blazed a first-time shot over the crossbar before Wednesday began to find their rhythm.
A period of pressure towards the end of the half saw goalkeeper Jacob Widell Zetterstrom finally called into action to deal with a series of high balls into his area.
Rohl introduced Liam Palmer and Josh Windass at the break and the latter’s presence created the space for Anthony Musaba to try his luck after meeting Bannan’s free-kick but the Dutchman’s shot flew high and wide.
Yates should have punished that miss but could not beat keeper James Beadle from close range despite being left unmarked.
Only the width of the crossbar prevented Warne’s team from putting the game to bed when Yates connected with Ben Osborn’s corner.
That was the cue for Bannan to punish Derby’s profligacy, curling a wonderful 64th-minute strike past Zetterstrom when the hosts failed to clear their lines.
Then, with almost the final kick of the game, Lowe fired home to shock the Rams.
The managers
Derby’s Paul Warne:
“We created enough to win the game handsomely. I know people are frustrated with me but I’ve even had members of their staff, not apologise to me, but say that we didn’t deserve that.
“We needed that second goal and we couldn’t get it. Yes, we lost a little bit of control but overall I thought we did excellently. The lads are devastated in that dressing room.
“They are lower than a snake’s belly in there so, because I think overall they’ve done really well, it’s up to us to stay positive and bring that positivity to them.
“Honestly, I don’t think I’ve ever felt this sorry from a defeat before because overall I thought the lads did great.”
Sheffield Wednesday’s Danny Rohl:
“After we went behind, step by step we came back into it. We got a little bit more control.
“But while I’m happy with the result, I’m not happy with the performance. We need to do better overall, especially in a division as tough as this.
“It is credit to my players that they came through. But I know we also need to improve and do better in certain aspects.
“Full credit to Derby, because I knew beforehand this would be a difficult game. They are difficult to play against, good on the ball and tough.
“But we showed a good mentality, not only to just come from behind but also to do that away from home.”