The Indiana Supreme Court recently issued an opinion holding that as a matter of law, when a sports participant injures someone while engaging in conduct ordinary in the sport, and without intent or recklessness, the participant does not breach a duty. This decision clarified that ordinary conduct in the sport turns on the sport generally, not the specific activity. This case, Megenity v. Dunn, can be found at http://www.in.gov/judiciary/opinions/pdf/02161701lhr.pdf
This decision means that a sport participant would need to show intent or recklessness on the part of the co-participant to have a viable claim for injuries under Indiana law.