Mystery continues to surround the nature of Ryan Crowley’s off-field troubles, with the Fremantle tagger likely to miss the start of the AFL season.

Crowley didn’t play in last week’s pre-season win over Melbourne, and he was again overlooked for Sunday’s NAB Challenge clash with Sydney at Drummoyne Oval.

The 31-year-old has largely been restricted to running laps in recent weeks, but it seems an off-field issue rather than injury has been behind his omission from Fremantle’s practice games.

Coach Ross Lyon was reluctant to delve into the issue when questioned about it on Friday, but he confirmed Crowley was ineligible for selection at the current time.

No time frame has been set for Crowley to return.

“He’s working through an issue that doesn’t see him available to play at the minute,” Lyon said.

“We’re really supportive, but I’m not in a position to comment any further.

“He’ll be training. Players are pretty resilient.

“We’re really supportive of each other.

“You wear the purple, you’re part of our family so to speak.”

When pressed on the matter, Lyon said: “Am I talking Swahili? I’ll be making no further comments.

“If you want to take it any further up the chain you can contact our CEO, but I’m sure he’ll have the same position.”

According to recent rumours, Crowley had contemplated retirement at the end of last season before deciding to play on in 2015.

The 2012 best and fairest winner has been one of Fremantle’s most consistent and resilient players in recent years.

The 188-game veteran hasn’t missed a match since 2011; forging a reputation as the league’s best tagger over the past three years.

Should Crowley be unavailable for the start of the season, Matt de Boer is set to take over the tagging role.

Defender Zac Dawson also appears set to miss the start of the season due to a lingering groin issue that has hampered him for most of the summer.

“He worked too hard off his own bat and it flared up his groins,” Lyon said.

“They take a while to settle down. It can be a bit bony, it can be adductors – it’s a complicated area. it’s not exact science there.

“But he’s back running and pulling up pain free, so from there he should make some rapid progress hopefully.”

Fellow defender Luke McPharlin will be rested for Sunday’s clash with Sydney, but star midfielder Nat Fyfe (hamstring) and defender Garrick Ibbotson (shoulder) will play their first match of the year.

Paul Duffield (rib), Michael Barlow (ankle), and Danyle Pearce (calf) are others who will miss the Sydney match.