Some wins are spectacular, some are memorable and some are fortuitous. This was definitely the latter for Leeds United, as betrayed by the sympathetic expression on Simon Grayson's face when shaking hands with counterpart Geraint Williams at the final whistle.
After as poor a display as United have managed all season, Max Gradel underlined just why the Elland Road crowd are so keen to see his loan move from Leicester City made permanent.
Collecting a short pass from Aiden White with just a minute remaining, the substitute unleashed a fearsome shot that flew past Jamie Jones in the Leyton Orient goal to clinch another vital three points for the League One leaders.
There was no doubt the last-gasp winner was harsh on the visiting side who had, particularly in the first half, played the better football.
In blustery conditions, Orient endeavoured to get the ball down at every opportunity in the opening 45 minutes and were rewarded with several good chances.
Leeds, by contrast, were ponderous and far too reliant on launching seemingly aimless long balls forward with even the likes of Robert Snodgrass, usually so consistent in a white shirt, having a distinctly below par night.
Only the introduction of Gradel just after the hour mark changed that as a sense of urgency was restored. Surprisingly employed initially up front, he was unfortunate to see one lobbed effort land on top of the net.
He then gave the otherwise outstanding Tamika Mkandwire a nervous moment with a driven shot that struck the defender's arm only for referee David Foster to wave play on.
The introduction of Max Grella from the bench meant a switch to the right flank and, at last, Leeds had some genuine width to test a compact Orient outfit.
Gradel thundered a shot that Jones did well to beat away with just three minutes left on the clock before, with the Geldern End imploring United to pour forward in attack, breaking the deadlock with a spectacular shot fit to win any game.
Returning to London without reward in the early hours of this morning will have been particularly hard to swallow for Williams's men, especially after being by far the better side in the first half.
Employing a slick passing brand of football that sensibly saw the ball remain on the floor in the blustery conditions, the O's made sure that lone striker Scott McGleish was afforded plenty of support when the visitors had possession.
These darting runs from midfield proved particularly difficult for Leeds to pick up and the upshot was Casper Ankergren having a far busier opening 45 minutes than his Orient counterpart.
The Leeds goalkeeper had to pick the ball out of the net after just five minutes after being beaten by Andros Townsend only for referee David Foster to rule that the free-kick by Sean Thornton that presented the Spurs loanee with the chance had been taken too quickly.
Only a last-ditch block by the Leeds defence then prevented Thornton from capitalising on some enterprising play down the right by Charlie Daniels and before Townsend's stinging 30-yard drive warmed the hands of Ankergren.
Orient's enterprising approach play then saw McGleish and Townsend presented with further chancesthat only two last-ditch challenges from the home defence snuffed out.
There was no doubt who was the more relieved to hear the half-time whistle with Leeds's only chance having come 10 minutes before the break when Sam Vokes shot wildly over after being picked out by a cushioned header from Jermaine Beckford.
It was the striker's 100th league appearance for Leeds and it seemed there would be no happy ending. That was, however, until Gradel struck to maintain the leaders' six-point advantage over second-placed Charlton Athletic.
Leeds United: Ankergren; Bromby, Kisnorbo, Michalik, Hughes (White 47); Howson (Grella 81), Kilkenny, Doyle, Snodgrass; Beckford, Vokes (Gradel 62). Unused substitutes: Martin, Prutton, Robinson, Somma.
Leyton Orient: Jones; Purches, Chorley, Mkandwire, Daniels; Smitgh, Summerfield (Jarvis 90), Thornton, Chambers, Townsend; McGleish (Scowcroft 60). Unused substitutes: Morris, Ashworth, Melligan, Demetriou, Cave-Brown.
Referee: D Foster (Tyne & Wear).
Collecting a short pass from Aiden White with just a minute remaining, the substitute unleashed a fearsome shot that flew past Jamie Jones in the Leyton Orient goal to clinch another vital three points for the League One leaders.
There was no doubt the last-gasp winner was harsh on the visiting side who had, particularly in the first half, played the better football.
In blustery conditions, Orient endeavoured to get the ball down at every opportunity in the opening 45 minutes and were rewarded with several good chances.
Leeds, by contrast, were ponderous and far too reliant on launching seemingly aimless long balls forward with even the likes of Robert Snodgrass, usually so consistent in a white shirt, having a distinctly below par night.
Only the introduction of Gradel just after the hour mark changed that as a sense of urgency was restored. Surprisingly employed initially up front, he was unfortunate to see one lobbed effort land on top of the net.
He then gave the otherwise outstanding Tamika Mkandwire a nervous moment with a driven shot that struck the defender's arm only for referee David Foster to wave play on.
The introduction of Max Grella from the bench meant a switch to the right flank and, at last, Leeds had some genuine width to test a compact Orient outfit.
Gradel thundered a shot that Jones did well to beat away with just three minutes left on the clock before, with the Geldern End imploring United to pour forward in attack, breaking the deadlock with a spectacular shot fit to win any game.
Returning to London without reward in the early hours of this morning will have been particularly hard to swallow for Williams's men, especially after being by far the better side in the first half.
Employing a slick passing brand of football that sensibly saw the ball remain on the floor in the blustery conditions, the O's made sure that lone striker Scott McGleish was afforded plenty of support when the visitors had possession.
These darting runs from midfield proved particularly difficult for Leeds to pick up and the upshot was Casper Ankergren having a far busier opening 45 minutes than his Orient counterpart.
The Leeds goalkeeper had to pick the ball out of the net after just five minutes after being beaten by Andros Townsend only for referee David Foster to rule that the free-kick by Sean Thornton that presented the Spurs loanee with the chance had been taken too quickly.
Only a last-ditch block by the Leeds defence then prevented Thornton from capitalising on some enterprising play down the right by Charlie Daniels and before Townsend's stinging 30-yard drive warmed the hands of Ankergren.
Orient's enterprising approach play then saw McGleish and Townsend presented with further chancesthat only two last-ditch challenges from the home defence snuffed out.
There was no doubt who was the more relieved to hear the half-time whistle with Leeds's only chance having come 10 minutes before the break when Sam Vokes shot wildly over after being picked out by a cushioned header from Jermaine Beckford.
It was the striker's 100th league appearance for Leeds and it seemed there would be no happy ending. That was, however, until Gradel struck to maintain the leaders' six-point advantage over second-placed Charlton Athletic.
Leeds United: Ankergren; Bromby, Kisnorbo, Michalik, Hughes (White 47); Howson (Grella 81), Kilkenny, Doyle, Snodgrass; Beckford, Vokes (Gradel 62). Unused substitutes: Martin, Prutton, Robinson, Somma.
Leyton Orient: Jones; Purches, Chorley, Mkandwire, Daniels; Smitgh, Summerfield (Jarvis 90), Thornton, Chambers, Townsend; McGleish (Scowcroft 60). Unused substitutes: Morris, Ashworth, Melligan, Demetriou, Cave-Brown.
Referee: D Foster (Tyne & Wear).
Thanks to Richard Sutcliffe of the Yorkshire Post for this match report
