Ryan was one of a number of players rumoured to be keen to exit the Dockers at the end of last season.

Brad Hill (St Kilda) and Ed Langdon (Melbourne) ended up leaving, but Ryan has decided to commit for the long term.

The 23-year-old still had one year to run on his current deal, and said his family gave him their blessing to stay in Perth for longer.

"I've got my family back home (in Melbourne) but when I spoke to them, we came to the conclusion that Fremantle gave me my chance - if it wasn't for Fremantle I probably wouldn't have been playing AFL," Ryan said.

"(Before) I was called out with pick 66 (in the 2016 national draft), I felt it was my last chance.

"And luckily enough they called me. I owe it to Fremantle and what they've done for me, so I wanted to sign on."

Champion Data rates Ryan as elite for intercept possessions and intercept marks, with the defender ranking second for intercept possessions in the AFL in 2019.

Ryan has played 49 games since making his debut in 2017.

He will form a key part of the defensive unit under new coach Justin Longmuir, who replaced the axed Ross Lyon.

Australian Associated Press