Sunderland 1 Derby 0:Anthony Stokes came off the bench to snatch a Barclays Premier League lifeline for Sunderland and further damage Derby's hopes of survival.
And Black Cats manager Roy Keane was rewarded with a clean sheet after his bold decision to drop Craig Gordon, the Scotland international he had made Britain's most expensive goalkeeper when he paid £9million in the summer.
Irishman Stokes struck in the third minute of stoppage time to deny new Rams boss Paul Jewell a point from his first game in charge and end his own side's eight-game wait for a victory.
The visitors turned in a spirited display on Wearside to resist Keane's men for 92 minutes, and on more than one occasion went close to ending their wait for a league goal, which now stands at 701 minutes.
All of the better chances came before the break with the visitors twice going close inside the final five minutes.
Kenny Miller forced a good save from Darren Ward, who was selected ahead of Gordon, and Dean Whitehead hacked a Steve Howard effort off the line.
However, the home side should really have been ahead in first-half injury time when Jones smashed a shot against the post with the goal yawning.
Ward dived full-length five minutes before the break to turn away Kenny Miller's shot after he had made the most of Danny Higginbotham's slip.
But the keeper needed the assistance of his captain two minutes later when, in an untidy goalmouth scramble, Howard toe-poked the ball towards goal, only to see Whitehead hack it off the line.
Until that point, Sunderland had enjoyed marginally the better of the game with 36-year-old Andy Cole going close to opening his account on his home debut with a looping 21st-minute header and Jones, Greg Halford and Carlos Edwards all firing just wide from distance.
However, Jones, who kept central defenders Darren Moore and Claude Davis on their toes throughout, should have given his side an injury-time lead when Bywater spilled Leadbitter's shot and he fired the rebound against the post from point-blank range.
Derby made a high tempo start to the second half as they pinned Sunderland back inside their own penalty area, Danny Collins conceding an early corner under pressure from Stephen Pearson and Halford deflecting a Matt Oakley shot just wide.
But the home side's response was swift and former Newcastle full-back Andy Griffin earned his money on 54 minutes when Leadbitter dummied Edwards' cross at the near post after Cole had done well to bring the winger into play.
Collins managed to ease Howard underneath Jay McEveley's deep 59th-minute cross, but the momentum was with Sunderland.
Keane introduced Michael Chopra as a 64th-minute replacement for the tiring Cole, and he inadvertently got the visitor's out of jail three minutes later.
Davis did well to block Leadbitter's shot and when the ball fell to Whitehead, he smashed it towards goal, but saw it hit Chopra and fly wide.
Danny Higginbotham managed to get a foot to substitute Craig Fagan's shot after he cut inside from the right wing 13 minutes from time with the game seemingly heading for a stalemate.
Stokes might have done something about that on 82 minutes after being slipped in by Leadbitter, but Rams skipper Matt Oakley got in a vital block to ensure his side's hard work did not go unrewarded.
But the Irishman made his mark at the death, reacting first to Bywater's double save to stab home a precious winner.