I really like national team sports, and I would like to see this, even tho I never really seen the anime series.
As I'm writting this, only the first episode was released yet, but my question is, do I NEED to watch all of it to understand this, or can I just watch this one, and maybe if I'm interested enough I can see from the begging.
Unfortunately, you don't really understand the connections between all of the characters if you don't watch the original series and the extras.
There are a ton of OVAs, but I think if you just watch the base series and the 2nd series you should be fine.
It helps you understand the moves and dynamic.
e- It's also part of the battle sports group, similar to Kuroko, but it predates it.
I'd say if you can't get into the first ~15 episodes of the first season, then it's probably not your cup of tea.