Garrick Ibbotson makes the surprise decision to retire at the end of the 2017 season.
The 29-year-old was coming out of contract this year and seemingly faced an uncertain future after being dropped to Peel after the Dockers' 100-point round-10 loss to Adelaide.
However, he broke the news to his teammates that he will hang up the boots after the Thunder's WAFL finals campaign.
"When you are looking at guys faces and telling them you are going to be out the door next year, it was never going to be easy," Ibbotson said.
"But as hard as it is to leave a football club, I think it’s the right time for me and I am happy with my decision."