Wade Small goal late in the first half earned Sheffield Wednesday three points at Colchester to pull his side out of the Championship drop zone.
The hosts went ahead in the opening stages when their leading scorer Kevin Lisbie found the net from close range.
But the visitors were level with their first effort of the game when Deon Burton headed home, before Small put his side ahead seconds before the whistle.
The Owls' victory puts them above Leicester and leaves the rock-bottom Us 10 points adrift of safety.
Colchester boss Geraint Williams named un unchanged starting line-up despite his side suffering a fourth successive defeat to Crystal Palace on Saturday.
Midfielder Sean McAllister and frontman Burton were recalled to Brian Laws' starting XI as the Owls went in search of a first away win since the start of November.
The visitors' survival hopes were boosted by their 2-1 comeback victory over QPR at the weekend but it was the Us who made a dream start.
Captain Karl Duguid provided the assist for Lisbie to slot home his 13th goal of the season in the fourth minute from just six yards out.
Midfielder Johnnie Jackson then attempted to double his side's lead with an effort shortly after the opener but Lee Grant made a comfortable save for the Owls.
The hosts continued to press with Duguid and Kemal Izzet both firing wide from just outside the area.
But the Owls pulled level in the 18th minute when Graham Kavanagh's accurate free-kick found Burton, who headed home past despairing Us goalkeeper Dean Gerken.
It got worse for the hosts as defender Chris Coyne was forced off due to injury, paving way for Bela Balogh's introduction.
Dean Hammond then volleyed wide for the home side before an effort from Small failed to test Gerken at the other end.
The midfielder then put his side ahead when he latched on to Marcus Tudgay's pass and slotted home from just inside the area in the 44th minute.
Colchester failed to carve out any real opportunities in an uneventful opening to the second half prompting Williams to bring Medy Elito into the action shortly after the hour mark.
Jackson then managed to get a shot away from outside the area but the midfielder's effort went right of the visitors goal.
The Us continued to try for an equaliser but Tommy Spurr managed to block Duguid's effort from range before Kavanagh cleared the skipper's corner.
Burton then looked to kill off the hosts with just over 10 minutes remaining but Gerken denied the striker's effort with his feet.
The hosts failed then failed to make the most of some late Jackson set-pieces leaving them looking destined for a return to League One.
Teams
Colchester Gerken, Ifil, Coyne (Balogh 24), Virgo, White,Duguid (Vernon 78), Izzet (Elito 62), Hammond, Jackson, Lisbie,Platt.
Subs Not Used: Bankole, Wordsworth.
Goals: Lisbie 4.
Sheff Wed Grant, Hinds, Beevers, Wood, Spurr,Songo'o (Showunmi 86), Kavanagh, McAllister,Small (O'Brien 90), Tudgay, Burton.
Subs Not Used: Burch, Wallwork, Boden.
Booked: Songo'o, Beevers.
Goals: Burton 18, Small 44.
Att: 5,086
Ref: Kevin Friend (Leicestershire).