Jon Rahm couldn’t explain why he picked up his ball without marking it on Saturday in the third round of the BMW Championship. (Andy Lyons)

By Daniel Rapaport
We’ve all done it before. Your ball is on the green, and you pick it up without marking it first. It’s one of the more common rules breaches in amateur golf.

But for a professional? That’s a rather large gaffe—and one Jon Rahm committed on the fifth hole Saturday at the BMW Championship.

A potentially costly one, too. Rahm shot a four-under 66 on Saturday despite being penalized for his mishap on 5. At two over for the tournament, he was just four shots back of the lead when he signed his card—very much still in contention to win, as Olympia Fields has been a bear all week. And in these $75 million FedEx Cup Playoffs, every single shot comes with serious financial implications.

So, how did it happen?

“Honestly, I can’t tell you,” Rahm said. “I hit it 30, 40 feet short, right on line, and was holding my marker in my pocket. Just went at it, and for some reason I picked up the ball thinking I marked it already. I was thinking of somebody else and something else … and yeah, I just picked up the ball without marking it. Simple as that. Once I replaced it, took the penalty and moved on.”

Rahm didn’t let the blunder ruin his round, playing his final 13 holes in three under to post 66.

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“I’m proud of being able to maintain my composure afterwards,” he said. “I think the most important shot of the round was that second putt, the six-footer for bogey … just more so proud that I was able to pull it off afterwards.

“I really can’t give you an explanation. It’s one of those things that happen in golf. Never thought it would happen in my professional career, but here we are.”

Needless to say, Rahm did acknowledge he had one wish for Sunday.

“I just hope I don’t lose by one. I’m just going to say that. I just hope. And if I do, well, very well my fault. It’s as simple as that.”