10-man Town fell to their second home defeat of the season – despite coming from two goals down against Braintree.
Goals from Dan Holman and Sean Marks had the Essex side ahead before Stuart Fleetwood saw red after picking up two yellow cards.
But roared on by a passionate home crowd, the Town fought back. Simon Ainge headed a Jake Howells corner before the break and substitute Dan Walker levelled it up moments after coming on as a second-half substitute.
However, the Hatters shot themselves in the foot from a set-piece as Braintree’s Matt Paine’s header from their only corner gave the visitors three points on a night of controversy at Kenilworth Road.
Town started the better and had their first real chance snubbed out by Braintree's back-line inside three minutes. Neat interchange down the left hand touchline between Howells and Northampton loanee Jake Robinson gave the former the chance to pick out Jon Shaw in the middle. A teasing cross was stolen off the toes of the striker before being cleared for a corner. The resulting set-piece again saw Town come close as a deep cross from Fleetwood was nodded down by Shaw to the feet of Robinson who lashed wide from 18 yards.
Despite Town's early dominance, it was the visitors who took the lead inside five minutes. Braintree's Holman's first touch control from an in-swinging free-kick gave him time and space to pick his spot. The Braintree number 20 then kept his cool, hammering into Mark Tyler's top right hand corner to give Alan Devonshire's men an early lead.
The Town looked to get back on level terms with Andre Gray leading the charge on 10 minutes. Connor Essam picked Gray out 40 yards from goal before the Hatters speedster flicked the ball over his shoulder and turned on the turbo to cut the ball back from the byline into the path of the on rushing Fleetwood who's outstretched leg came inches from pulled the Hatters back onto level terms.
Town continued to knock on Braintree's defensive door as Alex Lawless' tantalising cross toward the back post evaded everyone, including the Braintree stopper Daniel Naisbitt, who nervously watched the ball creep wide.
A possible penalty appeal was turned down by referee Lee Swabey as Fleetwood made a bee-line for the Iron goal. Fleetwood looked to have been tugged back by Adam Bailey-Dennis but to the astonishment of Town's leading goalscorer, and the entire Kenilworth Road crowd, the referee called the infringement in Braintree's favour booking Fleetwood for simulation.
Braintree came close to doubling their lead 20 minutes in as Bradley Quinton's long range effort ensured Tyler's concentration was up to standards. After a short free-kick worked its way to Quinton and there was only one thing in the midfielder mind but his tame effort was routine for Town's keeper.
It was end-to-end stuff as Fleetwood was again Town's architect weaved into the Iron area before his effort was deflected onto Shaw's head and into the Kenilworth Road end.
However, on 27 minutes the task became much harder as they were reduced to 10 men. Fleetwood's late challenge on James Mulley caused the referee to again look for his cards and seconds later Fleetwood was heading for an early bath.
The Town’s 10 then went directly back down the Braintree end to attempt and resurrect the scoreline. JJ O'Donnell's long range effort fizzed over Naisbitt's crossbar to reassure the home crowd this was far from over.
However with 31 minutes played Town's nightmare became a daunting reality as Sean Marks was allowed a free run through on goal before calmly nut-megging Tyler to double the visitors’ lead.
Again Town attempted to respond instantly, as Gray twisted and turned into the area finding only the body of Naisbitt in his way before Howells effort was deflected inches over the bar again by Naisbitt who was in scintillating form.
The Hatters then broke their first half duck to re-ignite the evening’s clash as Ainge's bullet header gave the Town faithful something to cheer about on 36 minutes. Howells' in-swingning corner was met by the unmarked Ainge who made no mistake with the header for his first goal in Luton colours.
Five minutes before the half-time interval the Hatters came close to level terms. Shaw's deflected effort inside the area looped over the crossbar before Ainge's acrobatic effort was off target and eventually cleared.
Corner after corner continued for Buckle's men as they went searching for an equaliser. Robinson's delivery from the left hand corner was met in mid-air by Essam whose powerful header hammered back off the post before Ainge instinctively stuck a leg out which trickled wide. With two added minutes chalked up by the officials O'Donnell fired wide from distance but with Town's pressure they would have wished for 20 added. Despite the Hatters’ onslaught the score at the break remained 2-1 in favour of the visitors.
A change in personnel for the 11 men of Braintree who replaced Nicky Symons with Daniel Sparkes at half-time. Town were looking for a change themselves but in fortunes rather than looking to the bench. Early chance fell to the Hatters as Shaw again found space in the Braintree area. Gray's searching cross found the Town target man but his header was safely over the Iron bar.
With 52 minutes on the clock Naisbitt came to the rescue for Devonshire's men. Shaw's flick on released Gray who surged through on goal before firing goal-wards from an acute angle. Naisbitt was down early to control the situation and keep his side on the front-foot.
As the Town continued to search for the equaliser, Howells cut inside to whip a deliciously weighed right-footed ball into the area with Shaw just a stud's length away from prodding past Naisbitt.
On 55 minutes there was a double change for the Hatters with Robinson being replaced by Yaser Kasim and Dan Walker on to replace Essam as Town looked to turn the deficit around.
It took less than three minutes for the substitutes to make an immediate impact with Walker sliding home from the edge of the area to level the game. The ball dropped kindly for Walker who's third touch since being introduced found the back of the net with a cute left-foot finish.
Gray then had half of those in attendance celebrating what they thought was a third. A jinking run by the forward saw him switch the ball from left to right before his effort deflected into the side netting for a Town corner. The resulting flag-kick saw Shaw's knock down bounce in the six-yard box into the hands of Naisbitt.
Braintree should have gone back n front on 64 minutes when Marks shot straight at Tyler with the goal at his mercy but two minutes later they did grab their third. With their first corner of the game Daniel Sparkes swung in delivery was met by Paine who rose highest at the back post to nod past Tyler to re-instate their one goal advantage.
As Town pressed for an equaliser it was Ainge who came close to again level the score. A free-kick by Howells found the defender who's flick on bounced inches wide of the far post.
There was another big chance for the Hatters to get back on level terms, falling again to Shaw. Gray again caused havoc on the right-hand touchline before hanging the ball up for Shaw who chested the ball down and hammered his effort into the body of Paine and out for a throw-in.
With the clock ticking down Shaw was sent tumbling on the edge of the box for a free-kick. Kasim stood over it before rolling it into the path of O'Donnell who smashed into the Braintree wall. Time was running out for the Hatters with chances becoming less frequent by the minute.
Lawless added his name to the chance list as he cut inside before his effort skewed wide on 80 minutes. O'Donnell sprayed the ball wide to Lawless who bundled his way into shooting range before firing wide.
It could have been curtains for Town seconds later as Tyler flapped at a free-kick under a challenge for Holman which bounced across the penalty area in-front of several Braintree bodies before rolling out of play for a goal-kick.
With five minutes left of normal time the visitors again came close to sealing the win off in style. Kasim's casual cross field pass was intercepted by Mulley who in turn slid the ball into the path of Holman who's audacious flick-up and volley crept over the crossbar.
Five minutes of added time was met with a rapturous roar from the home support as the Hatters kept pushing in search of an equaliser. Braintree held firm in the final minutes to secure their first ever win at Kenilworth Road and leave the Hatters six points off the summit before the visit of Nuneaton on Saturday.
TOWN 2 (Ainge 36, Walker 58) (Fleetwood sent-off 28)
BRAINTREE 3 (Holman 5, Marks 31, Paine 67)
Disaster for the Town. Braintree win their first corner and score from it as Iron defender Matt Paine rises highest at the back stick to beat Tyler.
Turn around complete here, Dan Walker, on as a sub moments before, sneaks a left-foot effort into the corner of the net. 2-2 Game on!
Game back on here as the Town have pulled one back. From a right-wing corner from Howells, Simon Ainge heads past a static Braintree defence.
Town really up against it now as Braintree have doubled their lead, a long ball over the top finds Sean Marks and he finishes coolly, nutmegging Mark Tyler. 0-2 and down to 10 men. Long way back for the Hatters here.
28 minutes played, the Town still trail, but worse still they have had Stuart Fleetwood sent-off for a second bookable offence.
Having bossed the early stages the Hatters are a goal behind. Daniel Holman takes a lovely touch just inside the 18-yard box to get away from his man before curling an unstoppable shot beyond Mark Tyler.
Goal updates and incident here.
Town: Tyler; Henry, Howells, Essam, Ainge; Lawless, O'Donnell, Gray, J. Robinson; Shaw, Fleetwood. Subs: Brill, Rowe-Turner, Lacey, Kasim, Walker.