ESPN has a surprisingly comprehensive JSON API that isn't locked down. If you're only using it for a hobby app, you won't run into any issues. It's been around for quite a while.
It's a "private" API for their website, but like I said it's been around for a while and using it in a hobby app isn't going to be an issue. Using it commercially is just begging for trouble, though.
As someone who maxed out multiple credit cards trying to pay for sports data, I know this pain all too well. If you're working on a hobby app, we give sports data away for free.