I chunked my 9 iron off the tee as one of our group joked about having a bad lie on the tee box. It landed well short of the green and based on the bounce it clearly hit a sprinkler head. As it catapulted towards the green we lost it but heard it hit something. One of my buddies said he thought it might have gone in. As we walked past we noticed the sprinkler head said "39" and we could not see the ball. Sure enough it was in the hole with a scuff from sprinkler head. May not have been the prettiest hole in one but it said 1 on the card.