The closest I have come to being KOed was at work about 10 years ago. I went to stop a shoplifter outside, he turned around and planted a hook on my jaw. The next thing I know I was wrestling with him about 20 yards from where he hit me. He hit me on the back of my jaw, it didnt hurt until I tried to eat solid food the next day. Then I felt it, doctor said I just bruised the muscles.