Seamus Power came into the final day of the PGA Championship six shots behind leader Mito Pereira.
Playing in just his second major after last month's Masters at Augusta, the Waterford man began with pars on the first and third holes, either side of a double bogey on the second.
He then got a shot back with a birdie on the fourth before an incredible moment occurred from his tee shot on the fifth.
Power's shot with a driver went left and hit a tree before hitting a spectator in the head and landing in his hood.
The 35-year-old looked somewhat confused when he came to see where the ball landed as a marshal removed it from the fan's hood to laughter and applause from the crowd.
Power went on to par the hole after dropping the ball.
One journalist who witnessed the shot, tweeted: "Seamus Power’s drive off the 5th tee went left, hit a tree, then hit this guy’s head before landing…in his hood.
"Meet Bryan Essex, who just took that golf ball to the noggin. No spare glove or autograph for him, but a volunteer did arrive with a few concession stand vouchers."
Speaking after his round on Saturday, Power said he felt confident going into the final day as he thanked his caddie Simon Keelan for his advice on the course.
He told Sky Sports after his round: "You are basically learning a new course, so I needed Simon's help a lot out there. We did our best with it. Those birdies on the way in made all the difference.
"You're still hoping no one gets too far ahead on the back nine. My game feels good and today seeing a few putts going in towards the end feels nice and gives you confidence and hopefully that continues into tomorrow."
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