Published: 00:00, 01 April 2014
| Updated: 18:17, 01 April 2014
Two late Luton goals sunk 10-man Dartford in front of a bumper crowd at Princes Park on Tuesday.
Mikel Suarez's first goal for the Darts had looked like it might be enough to secure a famous win in their battle for Skrill Premier survival.
But the home side, with their backs already to the wall, had Kenny Clark controversially sent-off and then saw victory ripped from their grasp.
Luton substitute Pelly Ruddock-Mpanzu scored a brilliant equaliser and Andre Gray headed home the winner on 86 minutes to the delight of the 1,800 travelling supporters.
The two changes to Dartford's starting line-up were both enforced, with on-loan Luton players Jim Stevenson and Alex Wall not allowed to play against their parent club.
Suarez took Wall's place up front, while Clark - a centre-back by trade - replaced Stevenson in central midfield.
The visitors dominated the early stages, roared on by their immense travelling support. Dartford had to defend plenty of set-pieces, with Suarez and Danny Harris feeding off scraps in attack.
Luton fashioned the first real chance on 13 minutes when danger man Gray got the wrong side of Mat Mitchel-King and forced a good low save from Alan Julian. The ball bounced up invitingly for Jake Howells but he couldn't keep his header down and the Darts survived.
Gradually, the home side began to gain a foothold. Lee Noble looked particularly lively down the right-hand side and when his low cross wasn't dealt with, skipper Elliot Bradbrook drilled a volley just wide of the post.
Noble then swung over a dangerous free-kick and the Hatters again looked uncertain in defence. The ball ran free in the six-yard box but Max Cornhill couldn't force it in.
Back came Luton, though, cranking up the pressure.
Cameron McGeehan sent a swerving shot wide and Paul Benson then saw his header strike the inside of the far post and bounce to safety. It was a real let-off for the home side.
But the Hatters' defensive frailities were exposed when Dartford took a 34th-minute lead. Noble's left-wing corner was powered into the net by the head of Suarez as the men in orange shirts watched on.
Cornhill's late runs into the box were giving the visiting defenders a real headache. His presence unsettled Luton moments after the goal and the ball dropped for Harris, who smashed his shot over.
And the midfielder then turned another Noble corner just wide of the near post.
Dartford ended the first half under the cosh but they defended stoutly to carry their slender lead through to the break.
The visitors started the second half as they'd finished the first - on the front foot. Alex Lawless turned Darts left-back Tyrone Sterling inside-out and delivered a low cross with which Benson failed to properly connect.
Dartford were working hard and they breathed a sigh of relief when Gray arrowed a low shot across Julian and just wide.
But then an unbelievable run from Sterling almost created a second Dartford goal. Sterling won the ball in his own half, beat two players, sprinted down the left wing and into the box before setting up Bradbrook, whose shot was blocked.
The work-rate of the Darts players was relentless, and it had to be, as Luton threw men forward. McGeehan got his head to a cross but Julian gathered easily.
It was all hands to the pumps for Dartford and their task got even harder 13 minutes from the end. Clark launched himself into a tackle on Lawless, caught him late and was shown a straight red card.
The orange tide kept rolling in. Gray looked certain to make it 1-1 but Julian saved at his feet.
However, the Darts keeper couldn't get near Ruddock-Mpanzu's unstoppable strike which flashed into the top corner on 83 minutes.
Luton, with their man advantage, knew the game was there for the taking now. Julian saved a Luke Rooney free-kick and the former Gills and Maidstone player then had another shot deflected onto the post by Bradbrook.
But the huge away support went wild when, four minutes from time, Ronnie Henry's deep right-wing cross was headed powerfully into the net by Gray.
It was so harsh on the Darts, who fought like lions all night.
Dartford: Julian, Burns, Mitchel-King, McAuley, Sterling, Noble, Clark, Cornhill, Bradbrook, Harris, Suarez (Collier 71mins). Subs not used: Swallow, Akinwande, Holloway, Woodyard.
Luton: Tyler, Franks, McNulty, Lawless, Howells (Rooney 66mins), Griffiths, McGeehan, Robinson (Ruddock-Mpanzu 57mins), Henry, Benson (Cullen 54mins), Gray. Subs not used: Charles, Justham.