When I was in Boot Camp on day one the instructors advised us that if we were to ever get with in arms reach of one of the Drill Instructors they would feel like we were about to attack them and they would feel forced to defend themselfs, so it was well known that if you were moving past a DI you would give them plenty of room or suffer the consequences. A day or two before graduation we were all in our Chucks so the recruits blended in rather well with the drill instructors. I was told by one DI to run to the other side of the squad bay and retreive something. So moving with some speed I ran through a group of recruits not realizing that there was a DI just on the other side of the group. The DI must have "felt threatend" because he quickly reacted by extending his right hand, in a fist, to the right side of my face, knocking me on my hind quarters. A few days later for graduation I was left with a slight, yet noticiable, bruise on the side of my face from "running into my DI's fist." After graduation I greeted my parents who were excited to see me and we walked through and I introduced them to my DI's. Right as I introduced my mother to the DI who I had had the run in with my mother noticed the bruise on my face and asked me what had happened right in front of him. His eyes got a little wide with surprise and looked at me with a sly grin. I quickly told my mother, "you know me, I am a clutz and ran into one of the racks." My DI slightly relieved gave me an even bigger grin which was the closest to a smile that I had ever seen him give in my three month stay.