Assistant manager Mark Kinsella has followed Colchester head coach Joe Dunne out of the exit door.
Dunne parted company with the U's following a run of five straight league and cup defeats and Kinsella has also left Weston Homes Community Stadium.
Chairman Robbie Cowling told the club website: "We would like to sincerely thank Mark for his hard work here.
"To some people, the last two years have been a struggle for Joe and Mark, but they have done a tremendous job in securing our League one status for the past two seasons.
"As earlier with Joe, I would like to wish Mark the best of luck for the future."
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