Ex-Exile Ryan Jackson came back to haunt his old club as Mikael Mandron also scored in a 2-1 victory for Colchester United at Rodney Parade.
The first-half yielded just the one shot on target, Joe Day superbly making a low save to keep out Brandon Hanlan.
And after County had missed a few chances early on in the second-half, Colchester made sure they were duly punished with two clinical finishes.
Jackson scored the opener on 72 minutes with a calm finish from 10 yards after being found unmarked by Mandron, who duly doubled the U’s advantage on 77 minutes.
Sean Murray’s delivery into the area seemed to take a glance off Mandron, who guided it past Joe Day with a fine header.
County substitute Shawn McCoulsky reduced the deficit on 85 minutes with his own header from a Dan Butler cross, but the Exiles couldn’t find the desired equaliser as they suffered a first home league defeat of the season.
Mike Flynn elected to name an unchanged side for the third successive League 2 game.
That saw the Exiles line-up in their usual 3-5-2 formation with Padraig Amond and Frank Nouble, who have 11 goals between them already this season, again leading the line up-front.
Colchester United manager John McGreal made three changes to his side that suffered a 1-0 home defeat to Carlisle United on the weekend.
And that saw a change in formation for the U’s with the visitors also electing to use the 3-5-2 system.
Defender Cole Kpekawa missed out of the matchday squad completely to be replaced by Kane Vincent-Young, while Diaz Wright also failed to make the trip to South Wales as Brandon Comley came in.
The final change saw Kyel Reid drop to the bench, with Ryan Inniss moving into the midfield.
And County really should have opened the scoring within the first two minutes.
Nouble, at his menacing best early-doors, charged past ex-Exile Ryan Jackson and into the area, before playing the ball across the area for his captain, but Joss Labadie was stretching when trying to connect and smashed it over the crossbar.
Colchester United swiftly created their opening opportunity of the night on four minutes, although Mikael Mandron’s header sailed well over the crossbar.
The visitors were growing into the game the longer it progressed, Labadie forced to hook a clearance away with several players waiting eagerly in the penalty area.
But that would unfortunately be Labadie’s last action of the night, being forced to withdraw due to what looked like a hamstring problem, Sean Rigg coming on in his place.
Nouble, Amond and Rigg all had shots blocked before the half-hour mark, as both sides were having healthy spells in the game.
Colchester were looking menacing on the counter-attack, especially with their evident ability of being able to spring 50 yard passes anywhere on the field.
David Pipe, who took the armband when Labadie went off, was doing an excellent job in breaking up the attacks should the visitors venture forward, by far the stand out man of the opening half hour.
But there was nothing Pipe could do to prevent the U’s from having a glorious chance on 33 minutes, and arguably they should have scored.
Brandon Hanlan was played through by a clever pass from Doug Loft, only to see Joe Day close the angle and make a clever low save to force a corner, of which Mandron headed over.
Immediately afterwards, Vincent-Young had to withdraw for the away side with an unspecified injury, prompting McGreal to throw on Lewis Kinsella in his place.
Rigg flashed an audacious effort from 50 yards wide on 42 minutes, before County again came close before half-time.
Pipe had again done superbly to charge down the right-hand side before looping an inviting ball into the area. But Amond and Nouble could only miskick the ball as it snuck out for a throw-in.
The indication of one minute of additional time couldn’t inspire either side to muster another chance, as both sides went-in to the dressing rooms with the game firmly in the balance.
County were looking a threat with their aerial presence during the opening 45 minutes, although couldn’t find a way through away goalkeeper Sam Walker.
It was evident that Colchester were bringing the physicality to the game, both strikers causing problems for the Exiles throughout, although the visitors could only manage the one big opportunity in the first-half.
McGreal was clearly unhappy with something from his side as he made his second substitution at half-time.
Lewis Kinsella entered the proceedings as Doug Loft made way, in a like-for-like change in the left-back position.
And after a slow opening to the second-half, it was the visitors who created the first chance on 54 minutes. Mandron again saw a header go wide as the visitors made the superior start.
Tozer saw a shot deflected wide for County’s opening chance of the second forty-five minutes, although Demetriou couldn’t quite connect to Dolan’s resulting corner.
And when County created their opening shot on target of the night on the hour, Amond was unlucky to be denied.
Pipe played a superb splitting pass into the path of the Irishman, only to see Walker tip it past the post. From the resulting corner, Tozer came even closer with a 20-yard volley that hit the post.
Then just sixty seconds later, Amond saw a header hooked off the line by Brandon Comley as County were really starting to turn the screw in the game.
Nouble blazed over on 64 minutes, before the Exiles could have been made to pay for not taking the chances as Mandron really should have done better when found in the area, only for the ball to come off his ankle to the relief of Day in the County goal.
And Day would have been relieved again on 71 minutes as Hanlan somehow headed over from just under the crossbar.
But they wouldn’t be denied again as Ex-Exile Ryan Jackson fired home in the area just a minute later. Jackson was found in the area by a delivery from Mandron, controlled himself before placing a shot through the legs of Demetriou and past Day.
The U’s could have extended their lead within 30 seconds of the restart, Hanlan being denied superbly by Day before again heading over from the narrowest of angles.
And all the Colchester pressure paid off for them as they grabbed their second of the night on 77 minutes.
Sean Murray whipped in an inviting delivery into the area, which Mandron seemed to get the faintest of touches to in order to guide it past a helpless Joe Day.
It was no more than the visitors deserved for a dominating period of play over the previous 20 minutes.
That forced Flynn into an attacking double substitution, Shawn McCoulsky and Lamar Reynolds both coming on in place of Dolan and Pipe, who was easily County’s superior player on the night.
And McCoulsky was intent on making a game of it, netting his sixth of the season with five minutes to go.
The striker was found in the area by a Dan Butler cross and duly provided the finishing touch to get County back into the game.
The U’s may have sealed the game right at the death, only to see Bennett superbly deny a swift Colchester United counter-attack.
Four minutes of added time gave the Exiles the license to really throw everything at the visitors, with McCoulsky coming so close in the second minute of added time, although couldn't connect to an Amond cross.
But Colchester defended resiliently from that moment on to see out a credible away victory at Rodney Parade.
County: Day, Pipe (McCoulsky 75’), Butler, Bennett, Demetriou, White, Tozer, Labadie (C) (Rigg 15’), Dolan (Reynolds 79’), Amond, Nouble
Subs not used: Bittner, O’Brien, Owen-Evans, Quigley
Colchester United: Walker, Inniss, Eastman, Kent (C), Vincent-Young (Kinsella 34’), Murray, Comley, Loft (Lapslie 45’), Jackson, Mandron, Hanlan (Odelusi 85’)
Subs not used: Slater, Gilmartin, Kabamba, Reid
Referee: Darren England
Attendance: 2,704 (136 away)
Next up for County: Mansfield Town (21st October) HOME