The dynamic defender will undergo an arthroscope to address a lingering knee injury.
"Andrew’s knee has been troubling him for a significant amount of the season but to his credit he has managed to play through the pain and make a solid contribution for our team," Football Operations Manager Andrew McKay told The Age.
"While we have reduced Andrew’s training load and managed the injury as best we can, we believe it’s in his best interests to have an arthroscope now to ensure it doesn’t get any worse."
Walker is a huge loss for the 14th-placed Blues, having averaged almost 23 disposals a game this season.
