Keith Andrews has left his position as first-team coach at League One-bound MK Dons "to continue [his] development and education within football".
The 35-year-old former Republic of Ireland international retired last summer to take up a role with a club he had two spells at as a player.
However, the Dons were relegated from the Championship this season.
"It has been a very tough decision but one that ultimately I believe will benefit me in the long term," he said.
"This is a club I have a lot of affection for and was delighted to be able to make the transition from a player to a coach. It has been the best place for me to learn my trade as an up-and-coming coach."