The Eagles scraped into eighth spot on percentage after a drama-filled win over Adelaide in the final round.
Port Adelaide will start as warm favourites in the elimination final, despite losing to West Coast earlier this year in Adelaide.
West Coast have struggled for consistency all season, and haven’t won consecutive games since three-straight victories from rounds six to eight.
Most pundits have already written off West Coast’s hopes of progressing deep into September, but Simpson isn’t treating the finals as merely a bonus.
“There’s no such thing as a free hit, is there?” Simpson said.
“There’s pressure on both sides. You can’t say we’ve got nothing to lose.
“It’s an elimination final. They’re really good games to play in, because it’s all or nothing.
“We know we’re massive underdogs and our backs are against the wall. But all that goes out the window in finals.”
West Coast’s biggest challenge will be curbing the influence of All-Australian ruckman Paddy Ryder.
The former Bomber dominated West Coast in the two meetings this year between the sides.
Simpson concedes Ryder probably picked up the three Brownlow votes in both games, and said his ruck duo of Nathan Vardy and Drew Petrie had a big job ahead of them.
“He is putting the taps where he wants,” Simpson said of Ryder.
“His work around the ground is also pretty special. And his ability to take pack marks really hurt us last time.
“We are going to do do everything we can to try to nullify that.”
West Coast have an excellent record at Adelaide Oval, winning five of their six games there.
Simpson said being on the road for a final allowed his team to escape the “fishbowl” environment of being an AFL player in Perth.
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