Hunting and fishing can be sports because if you make a competition there are absolutes, nobody gets judged for style, it's all about how many things you got and how big they are. That makes it a sport. Running and jumping are sports too, again dealing in absolutes of speed, height and distance. Figure skating is not a sport because there are no absolutes, the level of "athleticism" (which is nothing more than a combination of physicial fitness and agility) has nothing to do with it, the question is does the event's structure allow for you to point to an absolute and inarguable way of saying "yes these people were better at this today than those people", and when you've got judges including artistic presentation in the scoring system you don't have that, therefore it's not a sport and can never be a sport until they have an absolute scoring system that doesn't include the whim of the judges.
What are the "absolute standards" that measure a corner back's performance? You look at game film. If the guy can't cover, you bench him. Coach's call.