U21s record their first league victory.
Following the weekend U16s and U18s games, the U's have now won all three games against their Premiership opponents, scoring seven and not conceding a single goal.
Although the Swans improved in the second period, the U's defended excellently and protected Shaun Phillips throughout.
On top in the first half, they got their noses in front thanks to Freddie Ladapo's close range finish.
Colchester United's U21s registered their first win of the new league season, as they defeated Swansea City by a single goal on Monday night.
The U’s had the first half glimpse of goal as James-Lewis slotted the ball through to Ladapo, but his bursting run was stopped short by a fine interception from the outrushing goalkeeper Cornell.
The game was being played at a frenetic tempo in the first ten minutes and, at the other end of the pitch, Situ was up high to glance just wide of goal from a corner.
The big Swansea defender was in action at the other end of the pitch shortly afterwards, sliding in to block Massey’s shot from the edge of the box.
He could do little when the U’s took the lead on 16 minutes.
A good ball out wide was brought under control by Wright, who looked up and spotted two U’s men rushing into the area, and Ladapo made no mistake from inside the six yard box to put the home side ahead.
Hamilton went into the book three minutes later as he tugged down Donnelly just as it looked like he was escaping into the penalty area.
The U’s went close again on the half hour mark, with a free kick swung from left to right eluding everybody until it found Massey at the far post, but his swivelled effort went wide.
Ladapo went close to getting a second on 35 minutes, before Phillips was quickly off his line sixty seconds later to deny Donnelly.
The U’s led at the break after an impressive performance in the first half, but the visitors started brightly after the interval.
Despite their improvement, U’s goalkeeper Phillips was well protected by his defence with no clear cut saves to worry about.
Olufemi replaced Massey just after the hour mark and was brought down on the edge of the area just minutes later.
The U’s went close half an hour into the second period as James-Lewis sent Wright free and Olufemi nodded down at the far post. That ball back across, though, was just out of reach for Ladapo’s outstretched leg.
Swansea had a chance with just over ten minutes to go as Edwards got onto a long cross to the far post and lashed one back across the face of goal that could have caught any of three or four players on the way.
There was disappointment for the visitors late in the game as they were reduced to ten men after a flare up in front of the dugouts.
The ball got stuck in amongst a couple of tackles and, as Situ and James-Lewis got up, the Swansea man aimed a head at his U’s opponent, with the ref not hesitating to show him the red.
It was the last moment of the match as the U’s ran out single goal winners, with their impressive defensive display protecting Phillips in the goal throughout the match.
U’s: Phillips, Ramm, Hamilton, Eastman, Coker, Merrick-Lewis, Sanderson (Melaugh 80), Gilbey, Wright, Massey (Olufemi 62), Ladapo
Att: 240