Himmelberg is yet to recommit at West Lakes beyond this year, having last inked an extension in 2020 after just 17 matches with Adelaide, making his debut two years prior.
The 24-year-old has added another 20 games to his career tally since, at times struggling to cement his place in Matthew Nick's first-string forward line.
The situation could open interest from rival clubs, with the Dockers already tipped to be showing some level of interest in the Redland product.
According to SEN SA's Michelangelo Rucci, Fremantle have identified Himmelberg as a potential target to sharpen their speartip.
“Fremantle are putting together its list of how they overcome the issues of what they’ve got in attack, or don’t have in attack,” Rucci said.
“They think he’s the fit for them.
“He’s had five years at Adelaide, 37 games, 38 goals. We know he’s a tall player who can play forward and ruck – they want him as a forward. They desperately need to shore up their attack.
“He is growing with interest at Fremantle.”
The Dockers' key forward stocks are currently fronted by spearhead Matt Taberner, who has won the club's leading goalkicker award the past two seasons.
This year, ruck-forward Rory Lobb currently leads Fremantle's goalkicking tally after 20 rounds, having booted 30 goals from 17 matches as Taberner has battled ongoing hamstring issues.
Lobb's future at Cockburn is no certainty however, with the former Giant tipped to move back to the east coast this off-season.
The Dockers have also shown strong interest in Demons gun Luke Jackson, who can also add to their forward third while pinch-hitting in the ruck.