Reds suffered only their second defeat in nine games as leaders Luton showed why they are heading to League One and probably as champions.
The visitors struggled to cope with the home side’s movement and clinical finishing as Olly Lee (29), James Collins (45) and Luke Berry (56) had the game won by the hour mark.
It wasn’t all one-way traffic. Jordan Roberts hit the inside of the post at 1-0 and shortly before Luton’s second Reds were twice denied by goal-line clearances.
Collins rubbed salt into Crawley wounds with a 76th-minute penalty before Karlan Ahearne-Grant got the consolation Reds deserved with three minutes to go.
The outcome left the 267 travelling fans to reflect that they probably knew what sort of night it was going to be when it took three-and-a-half hours journey for some of them to get to Kenilworth Road.
Reds had to make a late change when Josh Yorwerth pulled out in the build-up which meant there were four changes to the side which beat Grimsby on Saturday with Cedric Evina, Roberts, Josh Payne and Mark Randall all recalled.
Reds weren’t quite makeshift but the balance Yorwerth provides as a left-footer in central defence was badly missed as Luton pressed from the start.
The home side’s seemingly unstoppable march towards promotion has stalled somewhat in recent weeks but they remain a formidable force and were soon on the front foot.
Glenn Morris had to make a good save in the first minute when Evina’s mis-directed header forced him to push the ball to safety and it set the tone for the first period.
Collins was denied by Morris at the end of a rapid counter attack in the seventh minute before he went even closer 11 minutes later with a low drive that skidded off the turf and came back off the left-hand post.
Lee let fly in the 23rd minute but Morris was equal to his shot before Luton broke the deadlock in the 29th minute. A Crawley move broke down and the hosts countered at pace again. Collins spotted Lee making a run down the right and set him up for an angled drive that beat Morris and flew in off the underside of the bar.
The hosts sensed blood. They won several corners and looked a threat every time they crossed the halfway line.
Reds, to their credit, tried to impose their passing game when they had the opportunity. Roberts fired wide when Randall set him up and three minutes before the break he came desperately close to equalising with a shot from the right-hand corner that left keeper Marek Stech motionless as it hit the inside of his right-hand post.
Harry Kewell would probably have settled for a one-goal deficit at the break but in the 45th minute Collins made it 2-0 with a finish from ten yards into the bottom corner which took a deflection off Lewis Young that wrong-footed Morris, after Reds had failed to clear Lee's corner.
Kewell made two changes at the break. Thomas Verheydt came on for Roberts and Doherty replaced Randall as Crawley switched to a 4-4-1-1formation with Ahearne-Grant playing off the Dutch striker.
Verheydt was inches away from halving the deficit nine minutes into the second half when he diverted Evina’s brilliant ball in from the left goalwards and it was hacked off the line. The loose ball fell to Boldewijn but his shot was blocked by keeper Stech in front of the home goal.
Luton responded by making it 3-0 two minutes later. Another swift attack ended with Berry finding space on the left-hand side of the box to lash a powerful right-foot shot past Morris and inside the left-hand post.
Twice in the game Reds had gone desperately close to scoring only to concede moments later but the visitors had given a much better account of themselves in the second half and on the hour, after Luton failed to clear a corner, Verheydt was denied for the second time in six minutes by an alert defender on the line.
Reds conceded a fourth 14 minutes from time. Lelan brought down Collins in the box and the striker struck his second of the night down the middle as Morris dived in vain to his right.
Reds deserved something for their efforts and they got it in the 87th minute when Ahearne-Grant controlled Jimmy Smith's pass and sidestepped a defender before scoring his third goal in as many games with a cool finish into the corner.
A disappointing night then and while there is no denying Luton’s quality, after six wins in the last eight no need for Crawley to panic either. The opportunity to start another good run comes on Saturday at home to Lincoln City.
Reds: Morris, Young, Lelan, Connolly, Evina; Boldewijn, Smith, Payne, Randall (Doherty 45), Ahearne-Grant; Roberts (Verheydt 45). Unused subs: Mersin, Tajbakhsh, Bulman, McNerney.
Attendance: 8020 (267 Crawley).