Published: 21:30, 03 October 2017
Max Ehmer struck a stoppage-time winner for the Gills on Tuesday night.
He stroked home a free-kick a minute into added-on time at Colchester to make it two wins from two in the Checkatrade Trophy.
The goal ended a three-game run without a goal for the Gills.
Caretaker boss Peter Taylor opted to rest some of his senior players, handing first senior starts to Finn O’Mara and Aaron Simpson.
Both held their own on the night infront of a sparse crowd at the Weston Homes Community Stadium.
The Gills lined up 3-5-2 with Tom Eaves back temporarily from his Football League suspension to play upfront alongside List.
Gillingham started the evening top of Southern Area Group B following the first round of matches. Colchester started their campaign with a penalty win over Reading under-21s.
Goalkeeper Stuart Nelson was back in the Gills squad for the first time this season, on the bench as cover for Steve Arnold. Three years earlier he had saved two penalties and scored the winner when the two sides met in the same competition.
List and Eaves combined early on, with the latter chasing onto a flick. List’s shot was deflected narrowly wide by home keeper Sam Walker.
Walker thwarted the Gills again midway through at the half, at full stretch to turn Sean Clare’s edge of the box shot over the bar.
Colchester lacked a bit of composure infront of goal, with efforts from Sean Murray and Cole Koekwa firing well wide of the mark. Their best chance came when Lewis Kinsella ran onto a knockdown but his low shot was comfortably gathered by Arnold.
Gills made a switch at the break, with List withdrawn and Josh Parker moving upfront, after playing right wing-back during the opening 45 minutes.
An early free-kick for Colchester in the second half saw Kinsella hit a deflected shot just wide.
The Gills had a great chance to open the scoring on the hour, with Darren Oldaker laying the ball off for Eaves, but the striker lifted the ball over the bar with just the keeper to beat.
Oldaker made a chance of his own moments later, showing great control to wriggle out of a tight spot, before running at goal and seeing his eventual shot deflected out for a corner.
A good spell from the away side saw Clare go close and Oldaker – who showed what he could do in the second half - sent another effort into the goalkeeper’s arms.
Colchester’s best chance followed but Arnold made a crucial save to deny Sanmi Odelusi from close-range. The ball ran loose for Murray but his shot curled wide.
The game looked to be heading for penalties but Ehmer fired in a free-kick, finding the bottom corner of the net.
Colchester: Walker, Kinsella, Kent, Kpekawa, Comley, Murray, Mandron (Senior 60mins), Vincent-Young, Odelusi (Slater 78mins), Guthrie (Kabamba 46mins), James. Subs: Gilmartin, Jackson, Hanlan, O’Sullivan.
Gillingham:Arnold, Parker (Nash 82mins), Simpson, Ehmer, O’Mara, Nugent, Hessenthaler, Oldaker, Clare (Chapman 73mins), List (Bingham 46mins), Eaves. Subs: Nelson, Tucker, Starkey, Cundle.
Attendance: 684 (69 away)