COLLINGWOOD pair Brodie Grundy and Taylor Adams face decisive weeks on the training track in order to prove their fitness to take part in Robert Harvey's first game as coach against Fremantle on Saturday.

Grundy will look to be cleared of a neck injury that kept him out of the Pies' two matches before the round 14 bye.

The dual best and fairest was taken to hospital as a precaution following the incident against Geelong three weeks ago and has since returned to running ahead of the impending clash against Docker Sean Darcy.

Adams also increased his training before the Pies' break and is pushing to play for the first time after re-injuring his knee against Port Adelaide in round 10.

The Pies will already be without Jordan De Goey through suspension and Darcy Moore, who will likely miss the remainder of the season, from the side that beat Melbourne on Queen's Birthday.

With Harvey's elevation to caretaker boss, midfield coach Brenton Sanderson has moved to defence to assume Harvey's open slot.

Development coach Scott Selwood will step up to take the reins of the midfield from Sanderson in a further growth opportunity.