Washington Redskins quarterback Robert Griffin III participated full in Friday's practice, providing another sign that he will start Sunday's game against the Minnesota Vikings. Griffin is still listed as questionable, five days after he suffered a mild concussion in a loss to the Atlanta Falcons. The rookie must still receive medical clearance. "Doctors make those decisions, we don't," Redskins coach Mike Shanahan told the team's web site. "That's why we run all these tests. But why would you not let somebody play if he's felt good right at the end of the game (and) every day until now? "If he has these tests after practice today and all of sudden he's not feeling good or something's wrong, obviously we're not going to take the chance."