DRAMA has filled the pre-match for Sunday afternoon's Western Derby with West Coast veterans Daniel Kerr and Andrew Embley late withdrawals after hurting themselves in the warm-up.

As expected Fremantle goal sneak Hayden Ballantyne was a late withdrawal with a hamstring complaint and has been replaced by Jayden Pitt, but the Eagles’ dramas in the warm-up have thrown the game's lead-up into chaos.

Embley injured his hamstring in the initial West Coast warm-up in the rooms and was replaced in the team lodged 90 minutes before the game by young defender Brad Sheppard.

That appeared to be the end of the drama but then it was revealed that Kerr had hurt himself on the field and his spot in the team has now been taken by Andrew Gaff.

Kerr had been building some strong form over the past five weeks in his return after almost 12 months out with a hamstring injury, but will be disappointed to not be able to take part in the big clash with Fremantle.

Gaff will now be the substitute for West Coast replacing Chris Masten who is in his first game back from a knee injury, and will now start on the ground.