ADAM Simpson says West Coast needs to break the duck away from home this season to break the unwanted pattern that is emerging between the Eagles' performances week-to-week.

The Eagles demolished St Kilda by 103 points at Domain Stadium on Sunday.

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But Simpson's reaction after the win said a lot about the Eagles' current predicament.

They continue to dominate at home and yet they have barely fired a shot away this season and he said the clash against Port Adelaide in round nine looms as a vital chance to break the cycle.

"It's a bit of a pattern isn't it," Simpson said.

"That's pretty obvious. We get another chance. We get a chance every second week.

"So we'll see how we go this week. We're not going to change too much. I think we're not far off.

"But until we break the duck on that one, you're going to keep asking questions and I'm going to keep defending them."

Port Adelaide suffered a fourth loss of the season to Carlton on Sunday and appear on paper to be a different challenge for the Eagles compared to their previous trips to face Hawthorn, the Sydney Swans and Geelong on the road.   

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But Simpson said the Power at Adelaide Oval was still a big task.

"I think Port Adelaide at home is still very strong force," Simpson said.

"I know the Cats have beaten them but I think it's going to be a tough one."

The Eagles are almost injury-free across their list at the moment and seemed to escape without issue from the St Kilda win. 

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Simpson said the Eagles' best 22 was pretty easy to select at the moment, which means high-profile recruit Lewis Jetta will need to spend more time in the WAFL. 

"It's not too difficult to pick the best 22 at the moment," he said.

"The form that some of our players are in and the form they need to stay in is pretty obvious. They're selecting themselves at the moment. 

"There's also some guys who have been inconsistent so we need to look at East Perth every week and see who is playing well there."

Jetta had 29 disposals for East Perth on Saturday in a 91-point win but Simpson said he needed to keep building.

"He's still got some work to do," Simpson said.

"But I was just pleased he got some of the ball and enjoyed himself and they had a good win."