Resurgent Coventry claimed their fourth win in five League One matches at the expense of Colchester.
Franck Moussa poked in a cross from Gary McSheffrey before William Edjenguele then headed a quick second.
McSheffrey had initially been adjudged offside in the build-up to Edjenguele's goal, but referee Trevor Kettle overturned the decision.
Tom Eastman's header made it 2-1, but Sky Blues top scorer David McGoldrick tapped in a third late on.
McGoldrick's 12th goal of the campaign (and his 10th in as many games) helped Coventry move above Colchester up to 15th in the League One table.
VIEW FROM THE DRESSING ROOM
Colchester United manager Joe Dunne told BBC Essex:
"I'm absolutely stumped. The second goal has completely changed the game.
"The guy who scored is not offside, but there's a guy attacking the ball and going into my goalkeeper who's in an offside position. How can he not be interfering with play?
"Generally I think officials have a hard enough job as it is, but we've had a couple of calls now, in the last three games, that have aided in us not being able to win.
"It's very disappointing because I think we've been in the game all night."
Sky Blues boss Mark Robins told BBC Coventry & Warwickshire:
"You won't see a better goal than our first one. It was outstanding. The second goal was a good finish and the third was clinical.
"They put us under a lot of pressure, but we dealt with everything they threw at us.
"Clinton Morrison came on and, at the end of a game, that could have been a story as we all know what he can do.
"But we held firm, broke away and scored a great third goal on a counter attack."