The Miami Dolphins saw enough potential in Marcus Vick to believe he deserves a chance as a free agent. Vick, the brother of Atlanta quarterback Michael Vick, signed with the Dolphins on Monday, agreeing to a free-agent deal after his many problems at Virginia Tech cost him a chance to be selected in the NFL draft. "As an organization, we did an enormous amount of research, including consulting with professionals in detailed, in-depth analysis to feel comfortable that giving Marcus an opportunity as a free agent is a risk worth taking," Dolphins coach Nick Saban said in a statement released by the team.