The Seahawks in the Carroll era don't strike me as stubborn at all. They've made it known any player can fight/win the starting job regardless of name recognition/salary/draft ranking. They've routinely traded down/given up their first round picks and are confident in being able to find the right type of a players for their system in later rounds. They've also drafted second round picks that were projected as 5th/6th rounders because of what they see in the player.
Thus the 1st round rookie tag doesn't mean as much as you might think. Carson could absolutely be their 20+ carries guy all year as long as he keeps performing but he needs to keep the turnovers down. I think he had multiple fumbles in preseason and one yesterday.. One of the two will emerge..or maybe a total wildcard will out of the blue