If you have a wireless network at home.
Go buy a ROKU player. ($70-100) depending on the model you buy. It's a one time purchase with no monthly charges unless you want to add on Netflix, Hulu Plus or things of that nature.
The Roku allows you to watch streaming TV from the internet.
Go online and sign-up for playon (about $50.00 for a lifetime plan). They also have a PlayLater option for about $30.00 more (lifetime subscription) that allows you use your computer/Roku like a DVR so you can record programming, save it and watch it whenever you like. I don't have PlayLater so not sure on the limitations, but I'm very happy with my Roku and PlayOn.
Check playon plug-ins and scripts online for "sports" channels. And/or darn near anything else you'd want to watch.
PlayOn channels/plug-ins/scripts can be watched through your Roku box on your TV, on your laptop, on your PC, on your Mac or on many phones. If you can get an internet connection, and you have the PlayOn software loaded to the device, you can watch it.
You just might find that you can get ALL NFL games, ALL MLB games, ALL NBA Games, ALL NHL games and more, for no additional cost.
A few caveats:
#1 is that if the HD thing is important to you, you can pretty much forget about it, even with fast internet, good router and HD television.
#2 is that this may be against the law. It's possible that uncle sam could somehow track you down out of the millions of others that are doing this successfully.
#3 is that sometimes you may need to try a few "links" to find your game before you get one that's streaming well.
#4 is that sometimes there can be some buffering that will be frustrating.
But, this is one way that could VERY, VERY LIKELY work to provide you with TONS of sports, plus movies, plus recorded programming, plus Live programming, etc. without a huge investment.
I do not work for or represent any of the companies mentioned above and I suggest you check the legalities of this. Then, if you are comfortable, watch away until your hearts content.