Mistakenly giving away the match play championship of my flight at my home course. I was three up with four to play. My opponent and I each hit bad drives. He hit into the large stand of tree on the left of the 15th fairway. I hit completely across the 16th fairway to the right. We eventually met again on the fringe of the green, he on the left, me on the right. He hit up next to the pin. I asked him what he was laying. He said 6. I was laying 3 so I gave him the putt without even walking up to see it. I got down in 3, at which point he said he took a six. When I asked him about saying he was laying 6, he said he thought I wanted to know what the next stroke would give him. I was so flabberghasted (and shaking with anger) that I marked him as having won the hole. As I continued to stew, after loosing the next three holes, I mistakenly congratulated him and turned in the card with him as the winner 1 up. In case you wonder why I couldn't get a grip over three holes, another incident at the 17th put me off my game. Difficult par 3 with creek right in front of the green. He hit first into the water. I took extra club to make sure to clear the water and pushed slightly into the trees beside the green. The ball usually drops out of the trees next to the green. Didn't see it, so said I would take a provisional. Opponent convinced me it would be fine, so I forgo the provisional. Got to the green and the ball had kicked through the trees and out of bounds on the other side of the trees (apparently the golf gods were getting back at me for the hole-in-one there on Mother's Day). Needless to say, once again my blood was boiling. I went back to the tee and hit two straight OB and conceeded the hole.