Mason Cox, the first American to become a regular AFL player, has been delisted by Collingwood after 139 games.
The 34-year-old has confirmed he won't be with the Magpies in 2026.
In a video on his Instagram, Cox thanked the club and supporters, saying he was "pretty excited about what's next".
The towering ruck-forward didn't confirm if he intended to retire or try to extend his career at another club.
"It's crazy to think that you'd never heard of a sport ... to then be a premiership player," Cox said. "Collingwood supporters are the best supporters in the world."
Cox famously debuted on Anzac Day 2016, kicking the first goal of the game in front of 85,082 people at the MCG.
A former college basketballer, Cox was signed by Collingwood as an international rookie in 2014 after impressing at two combines - one in Los Angeles, and the second in Australia.
After 20 games over his first two seasons on the Magpies' main list, Cox became a regular in 2018 as Collingwood shot back up the ladder.
In one of the most extraordinary preliminary final performances, Cox powered Collingwood into the 2018 premiership decider with a towering effort to help dethrone red-hot favourites Richmond.
The Magpies went down to West Coast the following week in a thriller, but Cox became a premiership player five years later when Collingwood defeated the Brisbane Lions in an epic 2023 grand final.
Cox became an Australian citizen in 2022 during a ceremony at the MCG.
Wearing goggles for his final few seasons due to a serious eye injury, Cox ends his time at the Magpies with 127 goals.