Fremantle are set to extend their trials for a trio of Supplemental Selection Period hopefuls into 2024 as the Dockers weigh up offering a pair of list spots for the new season.

The Cockburn club has two list vacancies for the SSP period, which will close in mid-February, after moving key forward pairing Josh Corbett and Sebit Kuek to the inactive list during the pre-season.

The Dockers added East Fremantle product and former Gold Coast flanker Jeremy Sharp to their list on the opening day of the SSP window in November.

Former Essendon forward Patrick Voss, local teenager Sam van Rooyen and Woodville-West Torrens youngster Max Beattie are all competing to join Sharp in on the Dockers' list as potential SSP additions.

Voss has made the venture west after spending the past two seasons on Essendon's list, where he went without an AFL debut but would enjoy a strong 2023 season at VFL level to earn best and fairest honours for the Bombers' reserves.

The 194cm key forward could be a strong contender for a list spot under Justin Longmuir given the absences of Kuek and Corbett in Fremantle's forward pack, who are dealing with knee/shoulder and hip issues respectively.

He has signed with VFL club Port Melbourne this off-season as part of a contingency plan if he is unable to land an AFL lifeline.

Voss could have some competition for a spot on the Dockers' list from van Rooyen, who was overlooked at last month's National Draft despite being among the leading tall forwards coming out of Western Australia's pathways.

Fremantle train-on player Patrick Voss at Dockers pre-season training, 2023 (Image via Twitter, Fremantle FC)

The younger brother of Demons spearhead Jacob, van Rooyen kicked 22 goals and averaged 8.7 disposals for Claremont's Colts side in 2023 and would play in all four of WA's National Championships matches.

Beattie, a 2022 AFL Draft prospect, was a shining light for Woodville-West Torrens in the SANFL this year as a teenager, averaging 14.3 disposals, 3.7 marks, 3.3 tackles and over a goal per game for the Eagles this year.

With the Dockers losing small attacking options Lachie Schultz and Liam Henry over the recent trade period, Beattie could be seen as a potential replacement in Fremantle's side.

All three SSP train-on players are set to return to training following the club's Christmas break, with AFL.com.au reporting Fremantle are yet to make a call on the trio and their pair of list spots.

The Dockers decided to keep their sole list spot vacant last pre-season despite having a pair of SSP prospects train during their summer pre-season program.

Victorian Liam Serong, the younger brother of Dockers vice-captain Caleb, was joined by WAFL star forward Sam Stubbs in pressing for an AFL contract before both were notified they wouldn't be handed deals for 2023.

The SSP signing window for next year is currently closed and will re-open on January 15 before expiring on February 19.