WEST Coast coach Adam Simpson is warning teams could be forced to start more than four players on the interchange bench at centre bounces to avoid giving away free kicks after seeing the new starting positions in action in Friday's win over Geelong. 

There was confusion during the Eagles' 34-point JLT Community Series win at Leederville Oval, firstly when the Cats gave away a free kick for their full-forward leaving the goalsquare early.

West Coast tried to play on from the middle but there was a lengthy delay waiting for players to get back into their zones inside the centre square and each 50m arc.

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Simpson sought clarification from the umpires' coaches before addressing his players at quarter-time.

It wasn't the only occasion when players had to adapt, with several racing from the bench into position just in time after goals were kicked, and the Eagles were penalised in the last quarter when a player was caught short.

"The free kick stuff is a work in progress for the AFL, I would've thought," Simpson said post-match.

"Penalising players for just not getting there in time feels a little bit odd, warnings, all those sorts of things. 

"I like the concept, but it would be great to work through that without having to stop the game for so long.

WATCH  Adam Simpson's full post-match media conference

"It's a combination of no runners allowed on the ground before a goal … so to get (players) on and off, sometimes it's impossible.

"You're just going to see extra guys waiting on the bench because they couldn't get the rotation.

"Those screens that they give us (to signal players when to come off) don't work in the sun, so we need to find a way."

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Cats assistant coach Matthew Knights was also a fan of the concept, but agreed it needed tinkering.

"I think the 6-6-6 is an excellent rule," he said.

"Just the logistics of getting everyone back into their positions post the centre bounce if a free kick is paid probably took a bit long at times."

Knights rued Geelong's slow start and wayward radar in front of goals in the 15.9 (99) to 8.17 (65) loss, but was pleased to get through relatively unscathed.

He downplayed a head knock suffered by veteran defender Harry Taylor, who played no part after a heavy hit in the first quarter.

"He's fine, I don't think there will be any issues moving forward with Harry," Knights said.

Geelong big man Esava Ratugolea showed encouraging signs in his first game since breaking his leg in round 10 last year, flying for marks with little regard for his safety.

"It was great tonic for us to see that in the box, because it just shows what type of character he is that he's not going to let an injury in the past hold him back," Knights said. 

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Geelong's top draftee Jordan Clark all but locked in a round one debut in a blockbuster against Collingwood with a standout display across half-back, collecting 21 disposals.

"He's just an unflappable type of character and he stood up on what would have been a big stage for him – his first game against the reigning premiers," Knights said.

The Eagles put Luke Shuey on ice at half-time after he racked up 17 touches, while Elliot Yeo and Jeremy McGovern also got through after interrupted summers.

WATCH  Matthew Knights' full post-match media conference

Simpson, who expected Andrew Gaff to line up in Sunday's pre-season Western Derby, liked what he saw from a youthful attack, with Oscar Allen (three goals), Liam Ryan (two), Willie Rioli, Jack Petruccelle and Jarrod Cameron hitting the scoreboard.

"I think it made me realise today how young our front half is," he said.

"We know what we're going to get from him (Allen) already. He'll have games where he doesn't have impact on the scoreboard, but he's so compliant with what we're trying to do.

"We've had some really good signs from him all pre-season."

Grand Final hero Dom Sheed was outstanding, finishing with 39 possessions and a goal as he looks to cement a regular spot in 2019, and Simpson was relieved to see his charges pick up where they left off.

"Really interested to see how we were going to go today – I was a little bit nervous to be honest because you just don't know where you're at," Simpson said.

"But I saw enough signs to suggest the work we've done we're heading in the right direction."