The club through chairman, Ambrose Rachier made the announcement in a statement on Thursday evening and said he had accepted his decision to leave.
The news comes after immense speculation about the coach's return.
“I have today received a resignation letter from coach Dylan Kerr. On behalf of the club, l accept the resignation because he has been good and candid enough. As per his letter, he is going for greener pastures and l want to wish him all the best,” Rachier said on the Gor Mahia website.
In his resignation letter dated November 15, Kerr indicated that he will be taking another coaching role for the new season and thanked all the club officials.
“With a very sad heart, l have decided to accept another coaching role for the 2018/19 season,” read part of the letter addressed to Rachier.
“I want to put on record that l thank you Mr Chairman for giving me the chance to work with you and more importantly for Gor Mahia FC.”
Kerr also thanked Gor Mahia players and asked them to remain focused on their careers.
“To players, all l can say is a thank you for being amazing – everyone played their part with fun, enthusiasm, hard work and most of all belief in what l demanded for both on and off the field. I hope you continue having the vision l constantly told you and always remember no regrets,” the letter said.
Being one of the fans' favourite, Kerr did not not forget to thank Gor Mahia fans.
“The Ko'galo faithful ‘Tibim’ Gorrrr Gorrrr Mahia, forever in my heart, forever family, forever friends you made all this work with your lust for passion on the field and your quest for us to be the best… You are the best.”
Rachier said, “As a club, we thank him for the level he has taken the club. We truly appreciate his work… he was understanding, respectful and a man of the people l must say. He did his work with passion and that helped the team to deliver good results.”
On his replacement, Rachier said the notice is rather short considering the CAF assignment coming up in two weeks. He said the current technical bench will continue handling the team as they plan to get another coach.
“We have a CAF match coming up on November 27 in Nairobi… the notice is short. We will not be in a hurry to get a replacement. We will continue with the current technical staff as we take our time to get a suitable replacement,” the chairman said.