J-school graduate here. A PR minor is probably a good idea, because if all else fails, you can transition into advertising and marketing as a copywriter or editor. Although to be honest, no one gives a damn about your minor. It's not really even worth putting on your resume.
If I were you, I would completely avoid the "small-town high school football columnist" route that so many aspiring sportswriters seem to take. That's a dead end these days, unless you're willing to take a "promotion" to fill the recently vacated role of Incarnate Word's basketball beat writer or something similarly boring and live in the middle of nowhere.
For now, get active on Twitter and start writing for as many publications as you can. And start a YouTube channel and talk sports. The bigger your online footprint is, the more likely you'll be able to land a decent gig after you graduate (or even before). Plus, if you have a built-in audience that you can bring with you to wherever you want to work, you'll have a huge advantage over other applicants.