Crouch had already been an unlikely starter for Friday night's round-one match against Essendon at Etihad Stadium, but the news is much worse.

Crows football boss Brett Burton revealed on Tuesday that as the onballer returned from his pre-season abdominal injury, he had suffered groin problems.

Crouch also missed the 2015 season with a foot injury and sat out the first month of last season as he recovered from a hamstring issue.

"Crouch has been returning from his abdominal strain and, in the process of that, he's flared up groin issues so he will be unavailable to play this week," Burton told the club website.

"Brad is obviously an important player to us and we take a no-risk policy with him given his previous history.

"He's missed quite a bit of training so we need to go through a re-conditioning phase with him now and that will be a six-to-eight week process."

The older brother of All-Australian midfielder Matt Crouch played 20 games last season - the most in his 61-game career - and was a key part of the grand finalists' midfield.

The Crows expect captain Taylor Walker (foot) and Alex Keath (ankle) to return in round two, while Riley Knight (foot) is three to four weeks away from resuming.

Australian Associated Press