What would be if, during a game of soccer, one person damaged his friend? Is there a difference between possessions, like glasses, and physical injury, like a broken leg? Is there a difference between sports, like soccer and boxing?
ב"ה Shalom, I will only give general guide lines how Halacha reviews such a case without getting into details. If your question relates to a specific incident which occurred a ruling should be given by a Rabbi who hears both sides. I will also not get into damage to possessions since in regard to that there are other factors which may apply, such as "Grama"=meaning indirect actions which have to be considered in each case. Rabbenu Asher, better known as the "Rosh" (1250 Germany-1327 Toledo, Spain) discusses a case of two people wrestling and one injured the other, and ruled that the person who caused the injury is exempt from paying any damages. The Rosh ruled so although, normally a person is fully responsible for damages he causes to another even accidentally, since in this case the damage is considered as something which was done in a totally unavoidable way, "אונס" in the Halachic terminology. He explains, that the wrestling was done with full consent from both sides knowing that when one tries to wrestle the other down to the ground it is impossible to fully control the force which will be used so he cannot control if the other may be injured. Since this was the intention on the outset of both sides, the injuring party is not required to pay damages and not held accountable. This ruling of the Rosh is brought down in the Shulchan Aruch, Choshen Mishpat (חו''מ תכא:ה). From here, I have seen Rabbis derive that the same would be the case in other sports in which people injure each other as a result of the game, such as kicking a ball or making your way to the basket people cannot control the force used and those participating expressed full consent to take part in a game where physical contact is sometimes inevitable. Therefore, if as part of the game someone was injured, the person who caused the injury would not be held accountable. This applies only if the injury was due to the game and not due to fighting or intention to harm the other person. All the best חג פסח כשר ושמח