He joins star midfielder Sam Mitchell battling an injured left ankle in a growing Eagles casualty toll.

Cripps is expected to be told this week his recovery will take six to eight weeks before he can resume full training and playing.

Dockers medical staff are also closely monitoring nagging knee inflammation to star midfielder Lachie Neale that the big possession winner suffered in Fremantle's stirring come-from-behind five-point win over North Melbourne on Saturday.

Classy winger Dockers Stephen Hill has already been ruled out of the derby with a hamstring strain he suffered eight minutes into the final term of the win over North as a candidate for best-afield before he hobbled out of action.

Mitchell, 34, is in a battle to recover in time to play in his first western derby against Fremantle in Perth on Saturday.

He is battling to clear significant bruising in bone low into his left leg and around the ankle, as well as cartilage and ligament damage.

The 2012 Brownlow medallist remains in serious doubt to return against a rejuvenated Dockers, after West Coast were hammered around heavy traffic and contested balls conflicts by revitalised Hawks.

Without Mitchell against his old teammates his adopted outfit was thrashed at contested ball possession wins by 22 at 163 to 141 and an overall disposals smashing of 97 as the Hawks rattled up 456 to the Eagles 359 touches.

Cripps, who turned 25 through Sunday's embarrassing outing against the imposing Hawks, is a loss to West Coast with his 74 disposals at an average of 15 a game and bagged nine goals and slapped on 24 tackles at around five an outing.

Mitchell's return will be critical in direct confrontation around the ball with champion Dockers play-makers Nathan Fyfe and David Mundy or even a showdown with emerging run-with specialist Connor Blakely.

Mitchell's race for fitness complicates Eagles selection dilemmas with coach Adam Simpson flagging prospects of changes after another meek surrender on the road and against a more ferocious opposition.

Hard-nut utility Mark Hutchings, enigmatic winger Lewis Jetta and almost forgotten key defender Eric Mackenzie are expected to make derby selection bids after stints back at WAFL alignment unit East Perth.

Dockers call-up contenders are expected to include Cam Sutcliffe and first-year centre-liner Harley Balic.

Balic, 20, missed the win over North with a hip injury after collecting 23 disposals in his opening two outings in wins over the Western Bulldogs and Melbourne.