West Coast champion Dean Cox is set for an elevation in his blossoming coaching career that further paves the way for the arrival of discarded North Melbourne big man Drew Petrie to the Eagles.

And passage for a stunning switch of feisty Fremantle small forward Hayden Ballantyne to West Coast is also opening up in this month's trade period.

Ballantyne, 29, is set to become the highest-profile Docker to ever join the Eagles after the 141-gamer asked to be traded with a year still to run on his contract.

The gutsy forward wants a swap to round out his flamboyant career after a season of internal unrest around Fremantle and prospects of a substantial rebuild of its playing stocks after a 4-18 season.