You shouldn't really expect a significantly more detailed answer given that you didn't tell us what make and model TV you're using. From a TV app perspective, it looks like only Roku-based TVs and Sony's latest Android-based models might qualify without an external streaming box.
From the NBC Sports Gold FAQ:
NBC Sports Gold said:
MY DEVICE ISN'T LISTED AS CURRENTLY SUPPORTED?
We are adding new devices all the time. Check back at www.nbcsportsgold.com regularly to see if your device has been added.
You log in to an account NBC sports.and then link the roku to that account..the roku provides an access code that links NBC sports to the app on the roku .roku is like a phone..it contains aps..not services..smartvs act in a similar manor
Roku apps "log in" to the provider's authentication server (after you've gone through the process of authenticating the device). If the log in is successful, you get to watch the channel. If it isn't, you don't get to watch the channel.
This is NOT like cable TV or satellite where a authorization is "pushed" to your box.