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Jon Rahm entered this week's U.S. Open as the defending champion. While that title hasn't been stolen from him yet, his golf ball suffered a different fate during Thursday's first round.

While on the 18th hole at The Country Club, the Spanish golfer saw his tee shot sailing left with the ball landing under the TV tower. As he began heading over to the area, Rahm saw two youngsters pick up the ball and run away with it.

The world No. 2 kept his cool and was granted a free drop. He had an unobstructed lane and went on to hit the new ball within 21 feet of the 18th hole. Rahm then made a successful birdie putt to help him finish the day at 1-under 69.

The situation was treated lightly, and Rahm even made light of the situation saying he knows what the thieves look like because they weren't exactly subtle while running away with his ball.

"I'm pretty sure I know who it was," said Rahm with a laugh following his round. "I recognized the two kids that were running the opposite way with a smile on their face. I am 100% sure I saw the two kids that stole it."