The Daggers were just minutes away from a famous league double over near neighbours Leyton Orient but had to settle for a point despite another strong away performance, writes Billy Taylor.
Substitute Scott McGleish slotted home a penalty in the 90th minute after Femi had bought down Paul Jose-Mpoku, the young left-back given his marching orders by referee Trevor Kettle for a professional foul.
John Still's side lined up in their familiar 4-3-3 away system, implemented regularly on the road this season, with Damian Scannell operating centrally in midfield and it was the former Southend man who created the opening goal.
Scannell received the ball just outside the box and his pass over the defence was reached by Danny Green who flicked the ball over Jamie Jones before tapping into an empty net, sending the 798 travelling supporters into raptures with just quarter of an hour on the clock.
It could've been two a minute later, Bas Savage winning the ball out on the right and breaking clear, only for his low cross to be hacked away with Jon Nurse, Scannell and Romain Vincelot in great positions.
The O's began to see a lot of the ball but spent most time in their own half with the Daggers, and especially Savage, Nurse and Green, pressing the defence superbly, denying them the opportunity to build up play from the back.
It was half an hour before Russell Slade's side created their first real opening, powerful striker Jonathan Tehoue beating the offside trap only to fire straight at Tony Roberts before Doe cleared bravely.
A succession of corners had the home fans on their feet but on each occasion the Daggers cleared their lines well, Mark Arber particularly impressive in the air.
Up the other end, the Daggers had a strong shout for a penalty. Peter Gain clipped a ball diagonally to Nurse in the box whose touch seemed to strike the hand of his marker. Kettle, however, waved away appeals.
Orient started the second-half on the front foot, Dean Cox cutting inside and beating 3 men superbly before testing Roberts with a strike which the veteran 'keeper tipped wide. Tehoue managed to get his head to the corner but his effort was just wide.
Slade's men were beginning to find openings that they weren't during the opening 45, getting the ball foward much quicker, Charlie Daniels this time in acres of space down the left but his low cross evaded the on-rushing Harry Kane by inches. That was to be Daniels last action, Jason Crowe coming on in his place.
The action was beginning to become end-to-end, Orient sloppy in possession in the middle allowing Gain a chance to motor forward, his shot narrowly wide with Jones diving at full-stretch.
Scott McGleish, scorer of the winning the goal when the two sides last met in FA Cup action, was bought on in place of Tehoue before John Still replaced the tireless Bas Savage with Marvin Morgan. The on-loan front man almost made an immediate impact, a clearance bouncing kindly off of the striker but Jones was out quickly to collect.
Nurse was causing the backline problems, firing an effort at goal from outside the box before latching on to Scannell's pass. Again, however, Jones was off his line to clear the danger.
Seconds the later, the game threatened to boil over. Cox, already being booed by the away fans after a somewhat over-zealous lunge on Scott Doe in the opening minutes, reacted petulantly to a well-timed challenge from Abu Ogogo. The right back won the ball perfectly, but Cox took offence and seemed to push the former Arsenal man before a mini-scuffle ensued. The handbags soon died down, Kettle booking both Cox and Ogogo for their involvement.
McGleish was beginning to have an impact on proceedings, dropping deep on two occasions to switch the play expertly only for play to break down to the frustration of the home following.
Up the other end, Morgan had a glorious chance to seal it. Green, in space down the right, drilled a perfect low cross into the box and, with the goal gaping, Morgan somehow managed to put his effort wide from 4 yards out. The substitute won't have a better opportunity to open his account for the Daggers.
The game would've been dead and buried, but 5 minutes later it was all-square. The ball was pumped into the box for M'Poku who managed to get goal side of Femi before being bought down. The left-back will now miss Saturday's clash with Sheffield Wednesday.
McGleish sent Roberts the wrong way from the spot kick, the home fans going wild and willing their side on to search for a winner in the dying moments.
Phil Ifil replaced Damien Scannell, the right-back slotting in on the left side of defence but his first action was to sell Arber short with a return pass which Cox latched on to, only to be hauled down by the Daggers skipper, earning the centre back a booking.
That was to be the last real action of a game which the Daggers were agonisingly close to winning.
They will rue Morgan's late chance but a point away to a side unbeaten at home since September is impressive and was the very least that their determined and energetic performance warranted.
Their work ethic couldn't be faulted and they will go into Saturday's game against Sheffield Wednesday full of confidence and looking to extend a 5-game unbeaten run which has seen them climb to a point above the drop-zone with games still in hand on their closest rivals.