I used to play lacrosse on a travel team. I was at a tourney in Alabama once and we were playing a team a bit older than us. In lacrosse, checking in the back is illegal. I was running down the right side, was about to pass to the attackmen to set up a play, when some idiot comes and backchecks me. Not only did he knock ME on my face, but he ran into the ref afterwords trying to slow down.. Guess what? I was called on for unnecessary roughness. Cuz apparently if my foot tripped him and sent him flying into the ref, regardless if I was ON THE GROUND, it's a tripping penalty. And they scored.