FREMANTLE has confirmed Ryan Crowley is 'dealing with some issues' and is not available for selection this weekend.

Crowley was left out of the Dockers' 29-man squad to face the Sydney Swans in their NAB Challenge clash at Drummoyne Oval on Sunday.

He also did not play against Melbourne last Thursday.

The 31-year-old was running laps at Wednesday's open training session and has missed a number of training sessions throughout the summer although there has been no suggestion that he has been carrying an injury issue.

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Coach Ross Lyon will address the media on Friday morning.

Earlier on Thursday teammate Garrick Ibbotson could shed no light on Crowley's situation, saying: "I'm not entirely sure where he's at.

"But he has been doing a lot of laps, and he is a proven player for us and a really fit guy.

"So it won't take him long to get up to speed. I'm not 100 per cent sure what's wrong with him. But he's looking OK running wise, so I don't think he'll be too far away."

Crowley is just 12 games shy of reaching the 200-game milestone. He has not missed a match at AFL level since 2011 but Ibbotson could not guarantee he would be right for round one.

"I'm not sure whether he'll be there round one or not," Ibbotson said.

"He hasn't missed a game for a long time. He's been a really good performer and a best and fairest at the club."

"But even when he's not out there training, he's really good for our younger guys coming through.

"He's really valuable around the guys who are in the midfield, and talking them through some different situations even when he's not out on the field."

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Fremantle do have Matt de Boer to call on as a run-with player in the midfield if Crowley is unavailable. De Boer has put in a phenomenal pre-season following an indifferent 2014 and has the fitness levels to run with the best midfielders in the AFL.

"I think Ross has said Crowls isn't going to be here forever, so it's always good while he's here to be able to talk someone like Matty de Boer through that role if it happens to work out that way," Ibbotson said.

"I'm not sure what the plans are with de Boer this year. If that happens to be the case, then Crowls will be there to help him out."

Meanwhile, Ibbotson will be joined against the Swans by teammates Aaron Sandilands and Nat Fyfe for their first pre-season hitouts, having passed a fitness test last Saturday.

He said he had "full faith" in his surgically repaired shoulder holding up to competitive football again.

"I never go into a game thinking I'm going to break down. If it does happen, I'll deal with it then. But other than that, I'm always confident playing, and I have no issues stepping out onto the ground."

Ibbotson has used Fyfe, who had the same operation, as a sounding board during his recovery.

"It was good to have a guy who's been through it before and hasn't had any issues since," Ibbotson said.

"I spent a bit of time with him going through a few strength exercises, but mostly it's the strength and conditioning guys helping me through."

Ibbotson said it was scary to think Fyfe, who enjoyed an outstanding 2014, could improve again but the Dockers think he will.

"He looks really good," Ibbotson said.

"Obviously he's put on a bit of weight and looks really strong. I think he's said he wants to be a more powerful athlete through the midfield, which is pretty hard to imagine because he's pretty good already.

"I think he can definitely improve. He's said himself he's not the perfect player. He's looking to improve his forward work a little bit, improve his marking, which is a strength of his already.

"And that explosiveness when he gets going will be really impressive."