David Helman of DallasCowboys.com:
I don’t think it’s even a question that Ezekiel Elliott will be first string, and I’d say that even if Darren McFadden was 100 percent healthy. To your second point, I don’t think “concerned” is the word I’d use, but it’s definitely something I’d be mindful of. DeMarco Murray got 83 percent of the carries for this team in 2014, and he finished with more than 400 total touches. That’s a tad much for anyone, let alone a rookie. Fortunately, the Cowboys have vastly superior depth at the position this year. I think Zeke will finish with roughly 280-300 carries, which would put him right around 18-20 per game. That should leave plenty of carries for Alfred Morris and McFadden to get involved.
It's doubtful that the Cowboys drafted Elliott #4 overall to let him sit behind McFadden and/or Morris as a rookie. As long as he doesn't fall on his face, he should be the workhorse, with McFadden and Morris sprinkling in as change-of-pace backs. McFadden’s offseason injury only serves to help Elliott’s chances of RB1 touches.