FREMANTLE coach Mark Harvey will continue to experiment with Chris Tarrant in the backline during this Saturday's NAB Challenge clash with West Coast.

The match, which is being staged to raise funds for sporting clubs affected by the Victorian bushfires, will be Tarrant's second of the pre-season after playing North Melbourne last week.

The former Magpie was part of a defence under siege against the Kangaroos, but Harvey said he would continue to use Tarrant in a variety of roles, including the backline this week.

West Coast will choose a forward line from Mitch Brown, Quinten Lynch, Josh Kennedy and Ash Hansen, with rangy forward Tony Notte also a chance to play.

"There'll be some good match-ups there for him. But as I said, at times he'll play back and forward," Harvey said from Fremantle Oval on Wednesday. 

"The next couple of games I'll have to introduce him to the forward line at times.

"I'm pretty keen on developing players to play both forward and back."

While Tarrant joins teammates Luke McPharlin and Antoni Grover as players the coach can swing end to end, captain Matthew Pavlich was not locked in for a specific role this season.

Pavlich, who has slimmed down over the summer and appears even more mobile, was the side's dominant forward last season booting 67 goals.   

But Harvey said Fremantle could definitely win games without the skipper in the forward line and he would again be rotated through the midfield.

 "Can I say how long he'll spend in the midfield? No I can't, because that'll vary from week to week," Harvey said. 

"It'll come down to a lot of our availability from a list point of view as to where we use him."

Harvey said his captain was only one or two kilos lighter, but had changed his body to suit the modern game.

"I think across the board you'll find guys that get along in their careers they sort of tend to understand that the game's changed and the intensity's going up," he said.

"You can't carry the same amount of weight that you have over previous years and you have to adapt to different circumstances. I think Pav's in that particular range at the moment.

"He'd only be about a kilo or two lighter, that'd be it. No more."

Harvey also weighed into the zoning debate, saying fears that the defensive tactic was set to stay were premature.

"What happens now is a lot of teams try things but they don't necessarily run with that in season," he said.

"Some clubs might use it. They might actually find it's a hindrance to what they want to do; hence they may drop it pretty quickly and resort to one on one.

"I hear a lot of people talking at the moment about how it's ugly to watch, but I don't think it will be. I think it'll be fascinating to see it unfold."