Johnson was gearing up to drive off the tee on the 13th hole at Augusta on Friday.
But, as he took his practice swing, he mistakenly clipped the ball with the tip of his driver.
The ball flew off the tee, hit the 13th hole marker and Zach Johnson saw it roll just a few yards in front of him.
Ian Poulter and Matt Kuchar found the error hilarious – but Johnson had golf rules to thank for his saving his blushes.
Because the 2007 Masters champion did not mean to hit the ball, there was no penalty for him to face.
That allowed Johnson to place it back on the tee, albeit sheepishly having embarrassed himself in front of his fellow pros.
Poulter was taken aback by the bizarre scene, admitting: “I have never, ever seen that.”
Fortunately for Johnson, playing partners Poulter and Kuchar were among only a few people who saw his mistake in person.
The 13th tee box on the so-called Amen Corner is the most isolated spot on the Augusta course.
And that ensured there were no spectators within 150 yards when the mishap occurred.
Golf enthusiasts across the world gleefully took in the moment as it was shown on TV.
Johnson, though, had the last laugh as he birdied the 13th following his error.
Johnson posted a +3 score of 73 on his second round at the Masters.
And that left the 43-year-old Iowa native in line to make the cut.
Francesco Molinari and Dustin Johnson led the way having posted scores of -7 and -6 respectively.
Ian Poulter, Jason Day, Phil Mickelson, Brooks Koepka and Jon Rahm made up the chasing pack on five under par.