Colchester United lead Swindon Town 1-0 at half time thanks to a goal in the opening minute of the game from Jacob Murphy.
With a win lifting them out of the relegation zone, the home side came roaring out of the blocks as Gavin Massey's cross from the right byline was tapped home by Murphy just 60 seconds after kickoff.
Tony Humes's side could have increased their lead even further just minutes later when Alex Gilbey collected George Moncur's pass and lashed a shot narrowly over the top of goal.
Moncur then fizzed a half-volley from the edge of the area over himself, but just as Colchester appeared to be in total control, Bongani Khumalo was called into action to make a crucial interception as Swindon launched a two-on-one counter-attack.
Nathan Thompson then skipped clear of the challenge of Matthew Briggs and sent a rasping effort towards goal that was kept out at full stretch by Sam Walker.
Walker than had to make another sprawling save to keep out an Andrew Williams effort on the stroke of half time.