WEST Coast coach Adam Simpson has declared Sunday's high stakes Western Derby is effectively a do-or-die final as the Eagles enter a must-win fortnight in their push for a top-eight finish.

The seventh-placed Eagles hold their fate in their own hands but have no room for error, with their low percentage meaning one loss would risk them being overtaken by Essendon or Richmond from outside the top eight.   

Simpson expected the Eagles would need to win both remaining clashes, against the Dockers and then Brisbane in round 23, to extend their streak of six consecutive seasons playing finals.

"It's probably not an eight-point game, it's a final, really. We understand that and I'm sure 'Longy' (Justin Longmuir) and Fremantle understand that as well," Simpson said. 

"This is one of the more important Derbies that we've all played in for a long period of time. It's high stakes this week.

"I’m assuming we’re going to have to win both games to play finals. That’s where my head space is, and that’s our mission.

"So that's why it’s not an eight-point game, this is a 'you need to win to play finals' game."

The Eagles last lost to the Dockers in round three, 2015, and will look to extend an 11-game winning streak against their crosstown rivals at an Optus Stadium that has no capacity restrictions.

A bumper crowd is expected after fans were locked out of the round seven Derby and COVID-19 precautions limited the crowd to 25,306 in the teams' only clash in 2020.

Simpson said the Eagles would not enter the game feeling as though they had the wood over Fremantle, who have changed significantly in the past two seasons under Longmuir.

"We’ve had a lot of success in the last eight years and you can draw on that experience in bigger games," he said.

"But I’m not sure if that makes a difference when you run on the field in front of 60,000 Fremantle supporters.

"We’ll need to deal with what’s in front of us and play in a way that is in the moment and what the game needs, not potentially what might happen around the game. We need to be concentrating on the moment."

The Eagles will be boosted by the returns of captain Luke Shuey, star forward Liam Ryan and defender Tom Barrass, but have lost veteran Shannon Hurn to a hamstring injury.

Premiership defender Liam Duggan's season also hangs in the balance as the club considers medical advice on his troublesome right knee, which will sideline him this week.

Simpson said the club had received a recent update and now needed to come to a decision in the coming days on "what Liam needs to do this year or in the future".

With selection a revolving door of injured players in recent weeks, Simpson said there was concern bringing multiple players back from setbacks but the club had learnt from recent experiences.

"They're exceptional players we're bringing in," he said.  

"How we manage their minutes is always a challenge, there's no easy way around that. But we're confident they've done the work and they're fit and ready to go.

"We go in with our fingers crossed a little bit, but also a little bit of confidence as well.

"These guys have been around a long period of time, so they're professionals and they wouldn't put their hands up if they weren't ready."