Ken McGregor has been ruled out of Sunday’s clash with Geelong at Skilled Stadium.
McGregor strained a quad early in the match against Port Adelaide and was unable to return to the field.
Ben Rutten (knee/calf) and Nathan Bock (groin) are still a chance to return to the side.
Crows midfielder Scott Thompson said injuries and doubt over key defenders means others must step up and play their role in the side.
“As far as injuries go, we’ve had injuries throughout the team all year,” Thompson said. “It has been well documented, (with the loss of players like) Ben Rutten and Nathan Bassett, who are All-Australian defenders, we’d love to have them all in the team but reality is they’re not and other blokes will have to come in, step up and do the job.”