Rosa, who would have become an unrestricted free agent at season's end, will remain at the Eagles until at least the end of 2016.

The 27-year-old opted to remain in Perth despite strong interest from clubs in his home state of Victoria.

Rosa played his 150th AFL match last Saturday against Fremantle, qualifying for life membership. 

In the lead-up to the Derby, Rosa spoke of his desire to be a one-club player. He also feels that there is success around the corner, and that Eagles fans should show faith in the players and the coaching staff despite West Coast sitting in 11th position with a 6-8 record this season.

"I was here in 2005 and 2006 when the club played in grand finals and won a premiership, and I have been around for some other exciting finals campaigns," Rosa said.

"I am confident we can build towards that with this group and I want to be a part of it.

"As a senior player, I believe I have an important role to play at the club and I have great faith in the playing and coaching group.

"Adam Simpson is in his first year as senior coach and he has changed a few things, with the game plan and training.

"It is taking a little bit of time for us to get on the same page with all of that, but we are certainly moving in the right direction.

"I have been here for 10 years and it definitely feels like home. It also feels like there’s some unfinished business."

West Coast football manager Craig Vozzo said the club was pleased that Rosa had turned his back on potential free agency to remain an Eagle for another two years.

"As a free agent he had a number of options, but we're pleased he's staying and he is an important part of our future," Vozzo said.    

"He has been an integral member of the team for a decade and, aside from what he offers on-field, he is highly regarded within the playing group."