Fremantle defender Joel Hamling could miss the first half of the AFL season after undergoing surgery on his ankle this week, while no time frame has been set on Jesse Hogan's return to the club.
The Dockers will enter the season missing a host of their best key position players, with Hamling, Hogan, and Alex Pearce all set to miss round one.
Hamling dislocated his left ankle in a training mishap last week and underwent surgery to repair the medial ligament.
Fremantle football operations manager Peter Bell wasn't confident that Hamling would be able to play in the first half of the season.
"I'm not ruling it out, but that would be optimistic," Bell said.
Bell had no updates on Hogan's potential return as the key forward focuses on his mental health.
Hogan has been granted indefinite leave from the club, and Fremantle will give him all the time he needs.
"I can't give you any updates on Jesse, except to say we are in contact and he's going well and we'll give you an update when we're able to," Bell said.
Pearce will miss at least the first few rounds while he recovers from ankle surgery, while goalsneak Sam Switkowski (back stress fractures) is set to miss a significant chunk of football.
Veteran midfielder David Mundy (leg fracture) and defender Nathan Wilson (toe) face uphill battles to prove their fitness for round one.
Bell backed Griffin Logue and Brennan Cox to fill the defensive holes left by Pearce and Hamling.
One major positive to come out of the summer for Fremantle is the progress of prized draft pick Caleb Serong, who shone in Friday's intraclub hit-out at the club's base in Cockburn.
The No.8 draft pick is firming for a round-one debut, and Bell was quick to lavish praise on the talented 19-year-old.
"He does remind me of Lachie Neale a little bit," he said.
"Coming through as a junior, he had a reputation for being very clean with the footy and very good around clearances.
"He's got that stocky build, and he won a number of clearances today."
Sean Darcy was held out of Friday's intraclub as a precaution, but Bell declared the ruckman a starter for next week's pre-season clash with Carlton.
Forward Matt Taberner came off late in the hitout, but Bell said it was just cramp.
Australian Associated Press