PROLIFIC wingman Andrew Gaff says West Coast's midfield will need to find another gear against Fremantle's powerhouse engine room if the Eagles are to continue their recent Western Derby dominance.

The Eagles ground out a fourth consecutive victory over Carlton at the MCG on Saturday, struggling to shake off the plucky young Blues before escaping with a 10-point triumph.

While Gaff didn't believe a lack of leg speed was an issue, he conceded the Eagles needed to lift against superstar Dockers skipper Nat Fyfe and giant ruckman Aaron Sandilands in the historic first derby at Optus Stadium.

"They're a quality midfield. They're renowned around the AFL as being one of the better midfields in the comp," Gaff said.

"You've got Fyfe, (Lachie) Neale and (David) Mundy, obviously Sandilands in the ruck is hard to combat, but I think we've won the last few (five) derbies in a row.

"So it gives us confidence that we're hopefully going to do the same.

"We know the game is won and lost in the middle. If we're a bit off like we were on the weekend it comes down to chance."

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Fyfe was at his destructive best in Freo's big win over the Bulldogs, racking up a career-high 43 touches and extracting 13 clearances.

His combination with Sandilands poses a major threat to the Eagles' hopes of consolidating their position at the top end of the ladder.

"We're going to spend a lot of time on (Fyfe) as we do with the other midfielders," Gaff said.

"We've got two quality ruckmen with Scotty (Lycett) and Nic (Naitanui) as we all know. If they can get us first hands (to the ball), it's up to us little guys to get the job done.

"You can't go into a game against Sandilands thinking you're going to win 100 per cent of the taps.

"It's that fine line between thinking of your own plans and trying to combat theirs."

A crowd of about 58,000 is expected for Sunday's clash, which is forecast to be a sell-out.

The Dockers haven't lost from three games at the venue, and the Eagles are preparing for an intimidating atmosphere for Freo's home derby.

"It will be tough. It will be weird. Obviously, it's going to be so much louder than what Domain Stadium was (with) 50,000 people hating us," Gaff said.

"It's almost like an interstate feel in terms of the crowd, but we've played the oval really well so far in terms of dimensions, so we expect to win whenever we play.

"It's going to be a big test for our maturity as a group and how far we've come as to how we deal with this weekend.

"It's probably more than another game with it being the first derby at the new stadium, but it's exciting."

Gaff, who declared he would be ready if Dockers tagger Bailey Banfield targeted him, has been buoyed by the Eagles' 4-1 start as he weighs up his future as a prospective restricted free agent.

"Really happy and it's exciting how the team's going at the moment," he said.

"A lot of young guys are playing really well and there's a lot of enthusiasm, so it's really encouraging."