I'd chime in and say it isn't an anime...
But given its excessive use of stock footage for plays, the female characters getting less competent and relevant as the show goes along, and the pirates all being good guys... It feels like an anime.
The thing that actually pushed me into saying the show is bad though is more because characters don't have emotional consistency at least when it comes to how the show progresses. Some of it can be excused in that they are playing them a bit more realistically (even if you DO get in a big fight with your best friend... it isn't likely you will stay mad at them forever), but other just feels like they dropped the drama for no other reason then they were tired of it... making the show feel rather shallow. Sure it has a LOT more drama then a typical show (everyone has their drama llamas) but that doesn't amount to much when they will so easily let go of it or bring it back... In otherwords it feels like "Drama as the plot demands".
What made it mediocre mind you was that not only were the characters rather stock... but the show had a very poor way at making you see or understand the flow of the game. They just hit the ball a bunch and MAYBE they are at the net, maybe not... This isn't aided by the stock footage. As well the enemy teams are almost always just generic players with helmets on and they never EVER try to pull you into the world of the opposing team (except MAYBE the pirates).
As well the power of the show the "Breath" becomes rather generic as the show goes along (Just think of it as magical sports playing powers). They don't focus enough on differentiating the characters, through their breath, and thus they often all feel the same. When they all have "Jump in the air and hit the ball really hard" powers, it kind of stops being special.
In otherwords it fails as a drama, it fails as a sports show, and it fails to live up to its own premise.