Matthew Broadbent and Aidyn Johnson have not been offered contracts by Port Adelaide for next season.
Broadbent, 29, notched 171 games after he was selected by the Power with pick No.38 in the 2008 draft.
The rebound defender missed the entire 2018 season due to a stress fracture in his foot before returning to play 10 games in 2019.
He was granted leave of absence to focus on his mental health in June.
Johnson, 21, played 11 matches since debuting for Port Adelaide in 2017.
“This is a tough time of the year where we farewell people who have made considerable contributions,” GM of Football Chris Davies told portadelaidefc.com.au.
“We thank both Matt and Aidyn for what they’ve done whilst at Port Adelaide and I’m sure our people will join me in wanting the best for them in the next chapter of their careers.”
Paddy Ryder and Dougal Howard have both requested trades to St Kilda.