What a shift in fortunes it was for Cowboys running back Gus Johnson over just a couple of hours last night. The Gilmer High School and Stephen F. Austin grad got to start for Dallas last night at San Diego, and scored a touchdown with some determined effort. It looked like a storybook scenario until later in the game when Johnson got injured, in what is now being described as a separated shoulder. That’s the kind of injury that could be season-ending.