Luton Town moved closer to securing a Championship play-off place as Harry Cornick's high-class header gave them victory at Cardiff City.
Substitute Cornick left Cardiff goalkeeper Dillon Phillips grasping at thin air as he expertly guided Robert Snodgrass' cross inside the far post.
Nathan Jones' team stay fourth in the table but stretch the gap to seventh place to six points.
Cardiff remain 17th after a third defeat in four matches.
Bluebirds boss Steve Morison will rue missed chances from Jordan Hugill and Isaak Davies in what was a tight contest for long periods.
But it was Luton who looked the more likely winners as the game wore on, with Cornick's moment of class clinching what may prove a pivotal victory.
The only disappointment for Luton was potentially costly injuries to goalkeeper James Shea, James Bree and Fred Onyedinma.
This was a meeting of two sides with contrasting ambitions, with Cardiff already glancing towards next season, while Luton focus on the possibility of achieving something extraordinary this spring.
The Hatters have not played at the highest level in three decades, but have given themselves a genuine chance of ending their top-flight exile just eight years after they were a non-league club.
It was hard to tell as much in a first half which was long on endeavour but short on quality at both ends of the pitch.
Luton's only sights of goal came from set-pieces, with Dan Potts heading over in the first minute and Reece Burke drawing a comfortable save from Phillips.
Cardiff threats were rare, although Joel Bagan's deep cross reached Rubin Colwill in space only for the Wales international to volley into the crowd.
The home side did create the one clear opportunity of the first half, when Hugill went through one on one after a tight offside call went his way.
But the on-loan Norwich striker was denied by a fine save from Shea, in what was his last significant contribution before he was forced off injured following a heavy collision with Tom Lockyer.
The game opened up in the second period, with Snodgrass' 20-yard drive forcing Phillips to paw clear before Cornick's audacious effort from outside the area dipped narrowly over the bar.
Cardiff responded on the counter, with Hugill's strong hold-up play allowing Tommy Doyle to square for Davies in the penalty area only for the substitute to lift his shot too high.
It was Luton asking the more difficult questions as the contest wore on, with Cardiff fortunate to avoid an own goal when Peter Kioso's cross hit Perry Ng and was somehow kept out by Phillips.
The breakthrough finally arrived 19 minutes from time, when Snodgrass' inviting delivery from the left was brilliantly guided home by Cornick.
Luton protected their lead with relative comfort, substitute keeper Harry Isted gathering Davies' low shot as Jones' side made it back-to-back victories over the Easter weekend.
Cardiff City: Phillips, Drameh, Nelson ©, Ng, Bagan, Wintle, Vaulks, Doyle (Harris 79’), Colwill, Doughty (Davies 20’), Hugill (Ikpeazu 81’). Subs not used: Luthra, Denham, McGuinness, Flint.
Luton Town: Shea (Isted 45’), Bree (Cornick 42’), Burke, Lockyer, Potts, Bell, Campbell, Naismith ©, Mpanzu, Onyedinma (Kioso 62’), Adebayo. Subs not used: Hylton, Mendes Gomes, Lansbury, Muskwe.