The Fremantle Dockers will focus on devising a future presence at Fremantle Oval after works officially begin on the club's new elite training and administration facility in Cockburn Central West.
WA Premier Colin Barnett, Fremantle president Steve Harris, City of Cockburn Mayor Logan Howlett and Minister for Sport and Recreation Mia Davies officially broke ground at the site on Wednesday that will become the club's base from 2017.
Rosich said the beginning of the works meant Fremantle could now focus on developing plans for its future in the port city.
"We're committed to maintain a presence at Fremantle Oval and that project will now begin in earnest," he said.
"We're looking at partnering with the City of Fremantle, East Fremantle Football Club, South Fremantle Football Club and Department of Sport and Recreation to get a great outcome there."
Rosich said it was a significant decision to move to Cockburn.
"Once you see the scope and scale of this site, the locality and the services and facilities that will be here, it ended up being a relatively easy decision but it was one considered strongly," he said.