Kennedy, who umpired 495 AFL/VFL games including five grand finals before retiring in 2011, had been head coach of the umpires since 2014.

His decision to quit has come as a surprise, with Kennedy to finish up in the role after round 10.

The AFL is yet to name his replacement.

"I would like to thank the AFL for the experiences and the opportunities that has been provided to me throughout my time in football," Kennedy said.

"I consider myself to be extremely fortunate to have experienced what I have in this extraordinary game.

"As a coach, I have not taken the job lightly and I sincerely hope I have contributed in a positive manner to make our game the best game it can be."

AFL football operations manager Steve Hocking thanked Kennedy for his service to the game over the last three decades.

"Hayden's expertise, passion, tenacity and professionalism has been a tremendous asset to both the AFL and the umpiring group," Hocking said.

"Over the course of his time in umpiring, Hayden has contributed to the progress of Australian Football through the implementation of a team-first approach to umpiring which is now prevalent at all levels of the game.

"It's not only important to acknowledge his contribution at the elite level, it is equally noteworthy to highlight his unrecognised support of community and state league umpires and their coaches, always generously giving his time to promote umpiring in any way that he can."

Australian Associated Press