The new injury is a pulled hamstring tendon in his left leg which Walker got two weeks ago in an exhibition game. Even hobbled he managed to score five points, although he was in for only five plays against Green Bay. That's why Detroit wants to keep the little man around, but the bad leg might in the end be decisive in persuading Walker to make good his decision to quit after this year. "You know," he says, "a linebacker can't be the politest man in town." With perfect decorum, the Doaker may get out of the man's way entirely.