This was the Alamo City Golf Trail Tournament Series in San Antonio. 185 yd par 3, tough pin location, back right corner. Green was elevated about 10 ft so I didn't actually see in go in.
Used my 6 iron, 712 AP2. Set up for a slight fade and hit a pure shot. The group I was playing with said "I think I saw the flag rattle", I thought he was joking, and when I didn't see the ball on the green, I assumed I went over. We walked up, looked in the hole, and well...the rest is history.
I golf so much by myself that I was terrified that my first Ace would be when I didn't have any witnesses. I'm glad I was able to do it during actual tournament play. Officials said it was the first in tour history.