When talking about acquiring Robert Griffin III to be the teams franchise quarterback, Mike Shanahan consistently emphasized that the rookie would not be able to do it alone. In particular, Shanahan told us over and over that over the years rookie quarterbacks have needed a strong running game and a good defense.Well, RG3 is not playing with one of the better defenses around but he does have the benefit of one the better rushing games in the league. The Redskins have 702 yards rushing, an average of 175.5 yards per game, tops in the NFL through four games.Griffin himself, of course, has contributed mightily to the rushing total. He has 252 yards on the ground, good enough for 17thin the NFL.But the main man toting the rock is rookie Alfred Morris. Many wondered why the sixth-round pick was starting over Roy Helu Jr. and Evan Royster, both of whom turned in solid performances as rookies in 9=2011. Nobody is questioning the decision now as Morris is fifth in the NFL with 376 yards rushing. His four touchdowns rushing have him tied with Arian Foster and Griffin for the league lead.The Redskins last rushed for over 700 yards in the seasons first four games in 1978. It has happened just two other times in team history, in 1945 and 1958.