Colchester cruised to a 4-0 victory to increase Stevenage's relegation fears.
Two goals in the space of three minutes put Colchester in charge early on. Blair Turgott tapped in from close range in the 10th minute after Stevenage keeper Chris Day had failed to hold on to Brian Wilson's high cross.
Day was at fault three minutes later when he failed to deal properly with Luke Garbutt's cross and Jabo Ibehre acrobatically volleyed home.
Colchester went further ahead nine minutes later when Craig Eastmond side-footed in from close range after Turgott had exchanged passes with Dominic Vose before firing towards goal.
Day palmed away Garbutt's excellent free-kick and although Francois Zoko headed a good chance wide, it was comfortably Colchester's half.
Stevenage improved after half-time and Luke Freeman was unlucky not to score when his shot was brilliantly saved by U's keeper Sam Walker, while Luke Jones' header came back off the crossbar.
But Eastmond tapped in substitute Sanchez Watt's low cross with 13 minutes remaining to wrap up Colchester's convincing win.