DERRY CITY's winless run stretched to five matches as substitute Seamas Keogh earned managerless Sligo Rovers victory with the last kick of the match at the Showgrounds.
Ruaidhri Higgins returned to the scene of his first win as Derry boss in his 50th game in charge but there was to be no repeat of that memorable victory as they slumped to a third straight loss.
With just two wins from their previous eight league matches, Higgins had called on his players to 'dig deep' to end a 'difficult period' in the season.
They certainly dug deep but they rode their luck at times and fell behind to Garry Buckley's close range effort from a corner kick after 21 minutes.
Jamie McGonigle got Derry back on terms on the stroke of half-time with a clinical strike after a comedy of errors in the Sligo defence.
Derry did have their fair share of chances in front of goal but found Ed McGinty in fine form as he denied Joe Thomson who found himself clean through on goal in the first half.
McGinty saved from Will Patching and McGonigle saw his effort go agonisingly wide of the post.
Sligo sensed they could get a winner and Brian Maher denied substitute Keogh a stoppage time goal with a point blank save .
However, the City stopper could do nothing to stop the former Republic of Ireland underage captain's blistering effort moments later as Sligo clinched a deserved victory in the fourth minute of second half injury time and the last kick of the match.
It was a missed opportunity with leaders Shamrock Rovers losing to Drogheda United but with one match remaining before the break Derry will be desperate to finish with three points in the North West derby on Friday night to arrest an alarming slide in form.
Higgins made two changes from the team which lost 2-1 to Dundalk three days previously with Danny Lafferty and goalscorer against the Lilywhites, James Akintunde both restored to the starting line-up. Brandon Kavanagh and Matty Smith both dropped to the bench.
Sligo, beginning their post-Liam Buckley era, were under the direction of assistant boss John Russell who made two changes from the team which lost to Bohemians. Paddy Kirk and Adam McDonnell replaced injured duo McCourt and Cawley.
Sligo burst out of the traps and should've done better when Keena was played into space down the right wing. The striker crossed dangerously into the Derry penalty area but Paddy Kirk miscued his first time effort and screwed it wide on three minutes.
Derry almost capitalised on an inswinging freekick from Patching on seven minutes but Boyce couldn't get his header on target and it went wide of the mark.
McDonnell tried his luck from an acute angle from inside the Derry penalty area and Brian Maher spilled it before eventually clearing the danger.
Keena did brilliantly to turn Dummigan 25 yards from the Derry goal and the Bit O'Red striker's curling effort from the edge of the box was deflected behind.
From the resultant corner McGonigle rose at the front post but didn't get enough on his defensive header and Garry Buckley got the vital touch at the back post to turn it into the net with his chest with 21 minutes on the clock.
Derry were unsettled and Karl O'Sullivan got in behind Lafferty on the right before bearing down on goal with Maher needing to parry away his strike.
Moments later Akintunde played Thomson through on goal on the halfway line and with Patching holding his run superbly in support to his left, the Scotsman opted to go on his own with Fitzgerald for company. As Thomson attempted to round Ed McGinty who advanced from his line, the Sligo stopper managed to smother the ball at his feet.
It went from bad to worse for City as Dummigan sustained an injury and was replaced by Kavanagh on 25 minutes.
O'Sullivan's well struck shot from 20 yards was fumbled by Maher and with McDonnell reacting quickest to the rebound, the Derry keeper got there first to claim at the second attempt.
At the other end substitute Kavanagh began a promising move which ended with Boyce's strike at the far post which was turned behind by McGinty.
Kavanagh nipped in front of his marker at the near post to meet Patching's corner kick with two minutes remaining in the half but his glancing header was saved comfortably by McGinty.
Derry were back on terms fortuitously on 44 minutes after comical defending by Sligo. Shane Blaney lost his footing and when Buckley's attempted clearance struck his teammate it fell kindly to McGonigle who swivelled before striking expertly into the bottom corner from 12 yards.
It was just the kind of fortune which had been eluding Derry in recent games and Higgins would no doubt have been relieved to go into the break level after a less than impressive first half display.
Sligo threatened to restore their lead at the start of the second half when Bolger played a neat ball into the feet of McDonnell and his powerful strike was turned behind at full stretch by Maher.
Kavanagh appeared to have McGinty beaten with a strike from the edge of the box but it was deflected just wide of the post with the keeper rooted to the spot.
Sligo enjoyed an encouraging spell and when Fitzgerald slipped the ball into the path of McDonnell, the winger's low strike was parried away by Maher.
The Bit O'Red continued to apply pressure and City failed to clear and Bolger then fired narrowly wide of the post.
Patching managed to get his free-kick over the Sligo wall on 70 minutes but McGinty was untroubled and gathered cleanly.
Patching picked out the run of McGonigle through the middle on 76 minutes and took a kick from Bolger for his troubles. McGonigle took a touch before his eventual shot was saved by McGinty.
The City striker did brilliantly to hold off his marker moments later when Thomson sent the ball into the Sligo penalty area. His shot on the turn had McGinty beaten but it bounced agonisingly wide of the net.
Ex-Derry defender Colm Horgan handled the ball right on the edge of the Sligo 18 yard box. Patching stepped up to take the free-kick but McGinty did well to palm away his effort at his near post with little under 10 minutes to go.
McGonigle did well to take down Thomson's diagonal cross on his chest but fired his shot on the half volley high and wide.
Maher denied sub, Keogh from point blank range deep into stoppage time before the same player fired in the winner with the last action of the match to seal a first win in six for Sligo.
Sligo Rovers: McGinty: Horgan, Blaney, Buckley (Pijnaker 70), Kirk: O'Sullivan (Heaney 82), McDonnell, Bolger, Morahan (Keogh 86), Fitzgerald; Keena; Subs Not Used - Brush, Banks, Hamilton, Byrne, Maguire, Barlow.
Derry City: Maher: McEleney (Coll 78), Toal, McJannett; Boyce, Dummigan (Kavanagh 25), Thomson, Patching, Lafferty (Smith 60); McGonigle, Akintunde: Subs Not Used - Gartside, Storey, McLaughlin, Malone, Porter, Mullan.
Referee - Paul McLaughlin.