Just days after St Kilda made the position held by Greg Hutchison redundant, the Tigers announced Monaghan would be leaving the club because of changes within the football department.
"For the past five years Ross has played an important role, particularly given the development of our new facilities, and we thank him for his loyal service," general manager of football Dan Richardson said.
"We wish him the best for the next phase of his career."
Geoff Walsh left Collingwood mid-season, while James Fantasia left the Western Bulldogs to join Hawthorn this year before stepping down because of illness.
Craig Cameron left Richmond mid-season to join the racing industry and was replaced by Richardson.
Monaghan crossed from Melbourne in 2008 to take up his role with the Tigers.
