U23s forward Ken Charles was on target for the U's in their latest Development League game on Thursday, as Charlton ran out 3-1 winners.
A tough first half saw them three behind at the break, with Charlton in front after just seven minutes, as Reece Hackett-Fairchild tucking the ball away into the bottom corner.
Eight minutes later and they were further ahead, as Alfie Doughty turned sharply to slot home a second.
Albie Morgan put the Addicks firmly in control as his shot from the edge of the area beat Ethan Ross to make it three.
The U's got back into the game when Charles' effort caught the wind and took it into the net.
Whilst Charlton were reduced to ten men with twenty minutes to go, the U's were unable to reduce the deficit further as the home side gained revenge for the 2-0 Colchester win earlier in the season.