Fyfe will join Matthew Pavlich, David Mundy, Aaron Sandilands, Luke McPharlin and Lee Spurr in leading the club.
"Clearly on the field he's shown he's becoming an elite player of the competition," Dockers skipper Pavlich said of Fyfe.
"The players have certainly seen that. But his level of influence and his ability to give feedback to his teammates are certainly some areas that he's improved in and grown in. I think he's got a fantastic understanding of the modern game and how our game plan exists and how to execute that."