Dolphins RB Jonas Gray, who scored on two one-yard runs, has the skill set to be a potentially effective short yardage back. But that alone likely won’t be enough to win him a roster spot, because the Dolphins believe Daniel Thomas can handle that role.
Thomas had strong 8 and 9 yard runs on the scoring drive engineered by Tannehill, while Lamar Miller had a nondescript night (two carries, six yards). Dolphins officials are much higher on Thomas’ potential than some fans are.
It sounds as if Lamar Miller may not handle the goal line duties, which would put a dent in his upside. He's the superior runner, so it's tough to see the team pulling him at the goal line for the plodding Thomas.