A late goal from Craig Slater earned Colchester United an unexpected 1-0 win at promotion-chasing Luton.
The midfielder struck with six minutes to go, producing an astute finish from 18 yards when a corner was cleared to settle an encounter that was low in quality.
United went close early on, Tom Lapslie's deflected shot claimed by Christian Walton, with Owen Garvan's wonderful volley inches wide.
Danny Hylton's 10th-minute effort was easy for Sam Walker, while Colchester almost broke the deadlock only for Denny Johnstone to scuff straight at Walton.
In the second period Hylton fluffed a great chance as he failed to get enough power on his attempt after Frankie Kent made a mess of dealing with a hopeful ball forward.
Garvan then completely missed his kick when well placed while Alex Gilliead's effort straight at Walker and Johnstone not far away either.
Johnny Mullins missed a golden chance, blazing woefully over from inside the box with 20 minutes to go, before Colchester won it late on thanks to Slater.
Hylton looked to have had his shirt pulled as he tried to net a late leveller, but Kurtis Guthrie could have made the outcome even more comfortable, denied by some valiant James Justin defending.