Originally Posted by tyu1314
I am just wondering is it a crime if you hurt your opponent really bad with tennis shot ? Like a big smash into him at the net, are they able to call the cop on you?
You are talking two different types of law: civil and criminal
There's a general acceptance of risk when playing a sport that players inherently assume. All you would need to prove is that there was no malicious intent to damage the other person.
As far as criminal goes, if a person knowingly and intentionally aims at and strikes a person with a ball, racquet, etc it could be interpreted as assault (the threat) and battery (the striking). That is the discretion of the executive powers to be (police/DA) on what they think the judicial process would determine.
As far as civil goes, you'd want to consult with your insurance agent. Intentional acts are generally not insured under a liability policy (homeowner, renter, umbrella). The plaintiff in a suit for intentional damages could ultimately sue you directly and you'd need to defend yourself and pay damages out of your own assets.
However, accidental damages caused in a tort against a claiming party are covered by insurance. Again, the plaintiff would have to explain how they "assumed the risk" of playing a sport within the rules and even by doing so were damaged by the defendant. Chances are, your insurance company would opt to settle with the claimant for a nominal amount to avoid litigation against you and the possibility of punitive (punishment) damages, which most liability carriers don't cover.
Nutshell, I don't think either would happen in the normal course of events of a tennis match/practice. Just ask yourself, "what would a jury of 6-12 of normal adults believe?" That would be your answer. It's America. Legislative, Judicial, executive checks and balances.