You are at a tournament, you accept the risk. Same thing in baseball or even Nascar and drag races. Crap happens.
I remember hearing about a case in Hawaii I believe where a golfer had an errant shot and it hit another player in the eye and he was blinded in that eye. The now partially blind guy sued and lost as it was ruled that golfers don't have that much control over the ball, unless it can be proven they intended to hit the person (that was the gist of it anyway). So, there is precedent in the courts in the US, but this is not the US.
As PA-PLAYA mentions, baseball can be really hazardous. We went to a local minor league game years ago and yes, it was a great view since it was a small field and you were "right there", but there was no net along the foul line (there was a small one behind the home plate, but it didn't extend all the way to 1st and 3rd bases) and I could imagine with people always looking at their phones or kids being kids and not paying attention, a foul ball could take somebody out by the head pretty easily.