HARTLEPOOL United top goalscorer Antony Sweeney pounced with three minutes left on the clock to end a six-game winless streak for Mick Wadsworth’s men.
The midfielder took his tally for the season to 11 with a typically instinctive strike and so sent Pools back up to 11th in League One.
The hosts switched to a 4-4-2 formation for the first time this season with Adam Boyd, making only his second start of the campaign, and James Brown paired in attack.
Andy Monkhouse was demoted to the bench following a poor run of form.
And the system overhaul saw Pools make a purposeful start to the game, Peter Hartley denied a sixth-minute opener when his header, from Evan Horwood’s corner, was blocked on the line by David Perkins.
Boyd then initiated a move which led to Paul Murray springing clear but Antony Sweeney but visiting stopper Mark Cousins was quickly off his line and smothered the midfielder’s shot.
Pools survived a scare at the other end when striker Steven Gillespie stooped to head narrowly wide from Lloyd James’ delicate, near-post centre on 27 minutes.
But the hosts finished the half the stronger of the sides and Murray forced his way through two challenges before seeing a 20-yard strike smuggled around the post by Cousins.
The second period continued in much the same vein as the first with chances very much at a premium at both ends.
Colin Larkin’s introduction just after the hour mark did at least spark some life into a laboursome Pools and the livewire Irishman immediately threatened with a strike which spiralled wide.
Larkin, injecting some much-need pace into the home attack, then burned by Matt Heath only for Cousins to repel his 12-yard strike.
Fellow substitute Monkhouse quickly recycled possession and teed up Ritchie Humphreys who was also then thwarted by the United stopper.
But the decisive moment arrived three minutes from the end, Humphreys’ free-kick dropping eight yards from goal with Sweeney swivelling his body to smash home beyond a helpless Cousins.
Pools: Flinders, Haslam, Collins, Hartley, Horwood, Sweeney, Liddle, Murray, Humphreys (McSweeney 88), Brown (Monkhouse 64), Boyd (Larkin 64)
Subs: Rafferty, Gamble, Yantorno, Donaldson.
Colchester United: Cousins, Beevers, Clarke, Izzet, Bond, Perkins (Wordsworth 60), Gillespie, Mooney (Odejayi 70), Coker, James (Vincent 79), Heath.
Subs: Baldwin, Henderson, White, Pentney.