Second half goals from Rhys Murphy and Matt Harrold consigned the Hatters to a 2-1 defeat from their trip to Crawley.
Cameron McGeehan had given the Town the lead thanks to a first-half header, but a rejuvenated home side delivered a sucker-punch display to sink the visitors.
McGeehan’s goal capped off a strong first period, but Luton were perhaps guilty of not making their chances count with little goal-mouth threat after the interval.
The defeat ended the Town’s five-game unbeaten run, as well as their promising away run which had seen victories in the previous two outings on the road.
John Still made three changes from last week’s victory over York, Stephen McNulty, Luke Guttridge and Josh McQuoid missing out to give starts for debutant Sean Long, Jack Marriott and Nathan Doyle.
The Hatters started as the better team, although goal-scoring opportunities were few and far between in the opening stages, as Craig Mackail-Smith in particular was limited to long-range attempts.
It left Mark Tyler enduring a quiet half, but the Town keeper was almost left red-faced when spilling a cross under pressure from Murphy, while the referee had also indicated a foul on the Hatters stalwart.
Marriott, in his first league start for the Hatters, was the latest to try from range, firing narrowly over Darryl Flahavan’s crossbar, but Crawley still harboured a threat with Murphy nodding over from Gwion Edwards’ left-wing cross.
Edwards continued to test out the Luton debutant, while Long was positive in attack himself, setting up Mackail-Smith on the half-hour mark for the striker to shoot a few inches wide after turning his marker close to the penalty spot.
The Town got their reward just moments later though, as Long again burst down the right-hand flank to send in a looping cross to the back-post. The Crawley defence seemed to have it covered, but McGeehan was on hand to nod home in spite of the efforts of Sonny Bradley on the line.
The goal continued the superb scoring record for the midfielder, netting his seventh in all competitions this season, and he came close to adding to his tally before the half was up, nodding wide from an Olly Lee corner before fizzing a 35-yard thunderbolt inches wide of a scrambling Flahavan’s left-hand upright.
Edwards, after being fouled by Long in a challenge which earned him a booking, posed more goal-mouth threat, snatching a shot wide when well-placed in the Town area, but the Hatters went into the break holding the advantage.
It took the Town time to get going in the second half, however, with the second half a rather stop-start affair thanks to the referee’s whistle, although Crawley grew in confidence as the game ticked over the hour mark in stark contrast to the first 45 minutes.
And they got their reward a few minutes later. Edwards, switched to the right flank for the second half, gained a yard on Dan Potts to whip in a cross for Murphy to head past a helpless Tyler among little pressure in the Town area.
The Hatters looked to gain an abrupt response, with Paddy McCourt introduced and causing an almost immediate impact as his right-wing cross found Marriott in the area. The striker was assumedly unaware of the acres of space he was given, electing to strike first time when a touch was possible, lashing over from 10 yards as the Town continued to disappoint in another frustrating afternoon.
That proved to be Marriott’s last moment of action, as John Still threw on McQuoid for the final 20 minutes with the game becoming increasingly frantic in Sussex.
Despite the endeavour, chances were at a premium until Crawley got their second goal. A Luke Wilkinson back header was half-dealt with by defensive-partner Scott Cuthbert, but the resulting knock-down from Murphy was rifled in from Harrold with just nine minutes remaining at the CheckATrade.com stadium.
The further setback slightly rejuvenated a Luton side who had looked a shadow of their first-half display, as the Hatters looked to keep their strong league form going.
Wilkinson had his header saved before Tyler was once again called into action, keeping out the long-range effort of ex-Hatter Luke Rooney, who came on as a second half substitute.
The lack of chances thwarted Town though, as the game went into five added minutes without the visitors really threatening since going behind. And there were to be no last-gasp heroics for the Hatters, giving Crawley all three points as the failure to win at the Broadfield Stadium continued.
The Hatters now head back to Kenilworth Road for their next two outings, with Leyton Orient visiting on Tuesday before table-toppers Plymouth making the visit north next Saturday afternoon.
Town: Tyler; Potts, Long, Cuthbert (captain), Wilkinson; Smith, Doyle, McGeehan, Lee (sub McCourt 66); Mackail-Smith, Marriott (sub McQuoid 71).
Attendance: 3,335 with a fantastic 1,412 supporting the Hatters.