Senior Coach Justin Longmuir will have several options when he sits down for selection this week, with Fremantle set to make at least two changes for Saturday’s clash with Richmond at Optus Stadium.

Sean Darcy (hamstring) and Jaeger O’Meara (suspension) will come out of the team that defeated Narrm in round 11.

The potential of rain adds another permutation to the mix, with Longmuir considering a smaller forwardline as Luke Jackson takes on the primary ruck responsibilities with Josh Treacy in support.

Jackson usually plays as a key forward that relieves Darcy in the ruck, but Longmuir was impressed with the 21-year-old’s efforts against Max Gawn and Brodie Grundy when Darcy was substituted off in the second quarter.

It means if Michael Walters is cleared to play, the small forward could make his return from a calf injury as a straight replacement for Darcy.

“I think ‘Jacko’ showed he was capable as the number one ruck when Sean went off,” Longmuir told 7NEWS.

“We just need to make sure we pick a second ruck and balance up our forwardline accordingly.

“It looks like the weather might set in on Saturday, so whether we go tall or small, we’ll make the decision later in the week.

“I thought (Josh Treacy) handled himself really well in the ruck when he had limited opportunity against Melbourne.

“We’ve done a fair bit of work with JT down at Peel as the second ruck, so he’s ready for it if his number comes up.”

To replace O’Meara, Longmuir was asked if would look at the likes of Will Brodie, Neil Erasmus or Travis Colyer in the midfield.

“I would probably add Liam Henry to that list as well,” Longmuir replied.

“We’ve had some really good form down at Peel and a lot of the guys are banging the door down.

“With Sean and Jaeger being out of the team this week, it opens up a few opportunities. There’s going to be good discussions to be had at match committee.”

Longmuir is hopeful that Walters will be available to face the Tigers and Darcy will return in time for Fremantle’s round 14 clash with GWS.

“Fingers crossed (Darcy is) only going to miss this week and he’ll be back for GWS next week,” Longmuir said.

“He trained really strongly yesterday, he’s running really well and he’s done a lot of work on that hammy since he injured it. We’re hoping next week he will be back.

“(Walters has) a pretty significant hurdle to get over tomorrow, but like with Sean, he’s done a lot of work, he’s rehabbed really strongly and he’ll throw his name into the mix.”

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