Former Wigan striker Martyn Waghorn scored a stoppage-time equaliser to earn Derby a barely-deserved point from a 1-1 Sky Bet Championship draw at the DW Stadium.
After hammering on the door for virtually all of the game, Wigan made the breakthrough with nine minutes remaining, when substitute Joe Garner volleyed into the roof of the net.
But Wigan had come into the game having thrown away an incredible 22 points from winning positions this term, and that tally increased by two when Waghorn was left unmarked at a corner to lash the ball over the line with seconds to go.
Wigan had started very much in the ascendancy, with Josh Windass unable to take delivery of a super ball from Lee Evans when he would have been in on goal.
A great run into the box by Nathan Byrne then promised much, but his left-footed shot was weak and straight at Ben Hamer.
The home side came within inches of taking the lead when former Derby winger Michael Jacobs released left-back Antonee Robinson, who shaped to cross but sent in a wicked shot that beat Hamer but struck the near post.
A brilliant short free-kick routine involving Anthony Pilkington, Sam Morsy and Kal Naismith released Windass, who fired straight at Hamer when he might have done better.
After hardly getting a kick in the opening quarter, Derby almost took the lead with their first effort on goal.
A free-kick from the left found Curtis Davies unmarked at the far post but he headed firmly into the ground and the ball looped up into the arms of Jamie Jones.
Waghorn then saw the whites of Jones' eyes, but could only drag his shot wide from a decent position.
At the other end, Windass did likewise before the Wigan forward was pulled back from a promising break by the whistle of referee Jarred Gillett, who really ought to have played advantage for a foul on Cedric Kipre.
Having not been at the races at all, Derby were almost gifted the lead within 15 seconds of the restart.
Naismith completely sliced an attempted clearance over the head of his advancing goalkeeper, with both men giving chase along with Waghorn.
The ball somehow ended up behind for a corner, with the Derby fans screaming for a penalty which never came.
Wigan then created - and wasted - a gilt-edged opportunity 10 minutes into the second period, when Evans set Windass away again in acres of space down the right.
With Pilkington totally unmarked and waiting for a tap-in, Windass managed only to slice the ball into the grateful arms of the Derby goalkeeper - the Wigan man punched the ground out of obvious frustration.
That was it for Windass and Pilkington, who made way for Garner and Joe Williams.
And Wigan continued to apply the pressure and Jacobs forced a brilliant save from Hamer.
The Derby defence eventually cracked nine minutes from time, when Jacobs found Garner, who hooked his volley into the top corner to the relief of most inside the DW.
But there was a sense of inevitability about what was to follow, with Waghorn's goal extending Wigan's winless run to 14 matches.
What the managers said...
Wigan's Paul Cook: "Chey Dunkley goes on, they put Curtis Davies up front…tactics and formations go out of the window at that point. It's mentality, it's strength of mind, it's whose marking who at the end.
"Someone's been marking Martyn Waghorn for 92 minutes, and in the 93rd minute, someone wasn't marking Martyn Waghorn. That's football, and I will take the blame for these lads, because the learning curve is quite brutal."
Derby's Phillip Cocu: "If I look at the game, in the first half we didn't take advantage of the space they gave us - especially at the back of their defence. They were pretty high up, but only on a few occasions did we try to run in behind. We tried to play, but we were sloppy with our decision-making on the ball.
"We've spoken recently about the need to have bravery in our play, but you also need to take into consideration the risk when you're in possession. In the end I think a draw was a fair result, and it's a positive and important result after so many recent defeats."