Crawley won their opening group game in the Checkatrade Trophy thanks to a headed first half goal by James Collins.
Reds took the lead in superb style after half an hour, the goal nodded in by James Collins following good work by Jason Banton.
Crawley made six changes to the side which lost 3-1 at home to Notts County.
Goalkeeper Yusuf Mersin, Joe McNerney, Enzio Boldewijn, Andre Blackman, Billy Clifford and skipper Jimmy Smith were all rested.
In their place were: Mitch Beeney in goal, Chris Arthur, Mark Connolly, Bobson Bawling, Aryan Tajbakhsh and Adi Yussuf. Louis Young wore the captain’s armband.
Reds had the first early chance as Josh Yorwerth dummied past an opponent and played in Adi Yussuf whose shot was blacked and then cleared.
Colchester wernt close when Macauley Bonne had a go at goal from outside the area and his shot flew only inches over the bar.
Reds then began to press forward and had two chances when Banton curled a shot at the keeper, following a one-two with Collins.
Then Banton enabled Collins to have a go and he cracked a powerful shot against the post.
The same duo combined again for the opening goal. Banton went on a mazey run and supplied Collins at the far post, who headed down into the net in the 33rd minute.
Colchester looked lively as the second half unfolded put pressure on the Crawley goal twice in two minutes.
First Drey Wright fired a long free-kick straight at Beeney, who dropped the ball before quickly recovering.
The visitors then forced a brilliant save from Beeney to deny Denny Johnsone, tipping his blockbuster shot on to the bar.
REDS: Beeney, Young, Arthur, Davey, Connolly, Banton (Clifford 70), Yorwerth, Bawling, Collins, Tajbakhsh, Yussuf (Blackman 75)
SUBS: Moris, Clifford, McNerney, Pappoe
COLCHESTER: Walker, Lapslie (Diaz Wright 61), Drey Wright, Szmodics, Vincent-Young, Wynter, Johnstone, Eastman (Peter 62), Bonne, Semble-Ferris, Kinsella
SUBS: Brindley, Porter, Dickinson, Barnes, James
REFEREE: Tim Robinson
ATTENDANCE: 881 (92 away)
Like our Crawley Town Facebook page for all the latest news on the Reds
Don’t miss out on all the latest breaking news where you live.
Here are four ways you can be sure you’ll be amongst the first to know what’s going on.
1 Make this website your homepage
2 Like our Facebook page at facebook.com/pages/Sport-Sussex
3 Follow us on Twitter @SportSussex
4 Register with us by clicking on ‘sign in’ (top right corner). You can then receive our daily newsletter AND add your point of view to stories that you read here.
And do share with your family and friends - so they don’t miss out!