STEPHEN Hill's nightmare run of quad injuries has continued, with the classy Fremantle half-back suffering a setback at training on Thursday.

Hill endured five stints on the sidelines last year due to ongoing niggles and managed just 13 games – his lowest return in his 10-season career.

The 28-year-old, who is eligible for free agency this year, went under the knife in December and was initially expected to miss the opening rounds of 2019.

However, Hill had made strong progress and was running powerfully on Thursday in a bid to be fit for the season opener against North Melbourne, but sustained another strain while kicking.

"We thought that (round one availability) was the case, but there was a little misstep yesterday where he's just had a slight strain, so that's put him back three or four weeks," coach Ross Lyon said.

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"It's disappointing, he's running fit, it was just a bit of a kicking issue.

"If it was any other player, definitely 21 days, with Stephen we'll have to assess it and see if it takes longer.

"Behind Stephen I think I'm next in line in the Docker community for disappointment."

Lyon planned for Hill to swap through midfield with Connor Blakely (hamstring) and help cover Lachie Neale's departure to Brisbane this season, but will be without both experienced players early in the campaign.

Superstar skipper Nat Fyfe will miss Monday's JLT Community Series clash with Collingwood at Joondalup.

Fyfe has had staples put in his elbow after undergoing surgery on an inflamed bursa and could face West Coast next Sunday, but his absence leaves Freo's engine room a significant challenge against the powerhouse Pies, and Lyon has some anxiety about his onball stocks.

"That's their absolute strength and AFL football is dominated by midfield. The Eagles' midfield stood up Grand Final day, didn't it?" he said.

"Nervous because we'd like to run deeper, but we're developing that depth of elite talent.

"So you had plans, Stephen Hill at half-back and Connor Blakely (midfield) and they can flip in and out and we know they're really top-flight mids.

"When you lose them, as a coach I'm more nervous about 'gee, we can get it done from here but we don't want another two or three to disappear', that would make it difficult."

In better news for Freo, young ruckman Sean Darcy is set to face Collingwood after escaping last Friday's intraclub with only hamstring tightness.

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The Dockers are already without veteran big man Aaron Sandilands, although Lyon was confident the 36-year-old was making "inroads" from his latest calf trouble.

"Obviously with Aaron out, he's (Darcy) really quite important to us," Lyon said.

"We've seen him play good AFL football against quality ruckmen, so we've got some real belief in him that he can stand up and he's a real competitor.

"He's probably got his nose in front (of Lloyd Meek and Scott Jones) at the minute."

Lyon hopes to alternate Darcy and Sandilands throughout 2019, and was excited by genuine competition for spots among his talls after Jesse Hogan and Rory Lobb's off-season arrivals.

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"As a match committee, we haven't had to make really many hard decisions in those areas for a long time," he said.

Hogan is expected to play both JLT matches after excellent progress from his navicular stress fracture, while injury-ravaged Harley Bennell is back running after avoiding yet another calf strain at training last week.

"It was frustrating, because December 16, our last session (before Christmas), his output through the midfield was greater than Nat Fyfe, and Nat had a good summer, so that gives you context where he got himself to," Lyon said.

"Unfortunately, post-Christmas that's just slid a bit in regards to those slight reoccurrences."