It's not often that your brother will tell you to go jump in a lake, and you'll do it.
But that's exactly what happened to Austin Johnson on Friday during the second round of The Players Championship at TPC Sawgrass, and with good reason. It saved brother Dustin two penalty strokes.
In one of the odder situations that can crop up on a golf course, Dustin Johnson had marked his ball on the fourth green, near the edge where water comes into play. Somehow while trying to toss the ball to his brother, who caddies for him, the ball slipped out of Dustin's hand, went over the railroad ties and rolled into the lake.
According to Chip Essig, 2011 National PGA Golf Professional of the Year and Vice Chairman of the PGA of America's Rules Committee, a couple of Rules then came into play.
"Rule 16 states that if you lift the ball on the green, you've got to mark it and the ball's got to be replaced," Essig said. "And Rule 15 tells us we can't substitute a ball in that situation. There are instances where you can replace a ball. Unfortunately, picking it up off the green to clean it and putting it back is not one of them.
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"You've got to put back the same ball you lifted. ... There used to be no way to get a ball back into play if you lost your original ball like that."
If that happened in the past, the player was disqualified, Essig said. Since the Rules were modified, it was changed to a two-stroke penalty for substituting a ball.
"Obviously, Dustin really didn't want the two-stroke penalty so he made his brother go down in the lake and find the ball," Essig said.
So as Dustin Johnson, fellow competitor Bubba Watson and a Rules official looked on, Austin climbed down into the water -- with sneakers on -- and lo and behold, found Dustin's ball on his first try.
The whole episode was caught on camera.
"A lot of times those lakes have enough slope in them that when the ball goes in, it rolls five or six feet further down," Essig said. "And there's a good chance there's a lot of balls in there. The fact that they pulled up a ball and it was his, is pretty lucky, too.
"The other thing that I'd be concerned about -- there's alligators in those lakes."
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Why does Rule 15 exist in the first place? Essig explains.
"You've got to finish the hole with the ball you started with," he said. "They don't want a ball that you can hit off the tee that doesn't spin very much and goes farther, and then a ball you can hit off a fairway that spins a lot so you can stop it. And then you get to the green and get a ball that hasn't been hit at all that should be more round -- truer -- to putt with.
"They want you playing the game with one ball."
However, there are exceptions to the Rule. Essig said because of hazards, it's impractical to require golfers to find every lost ball. So a ball can be substituted in certain situations. If the ball goes in a water hazard, you can drop any ball with a one-stroke penalty. Same with the unplayable ball rule. You can also switch out a ball that's damaged in the course of play.
So the lesson to be learned?
"Never throw your ball to your caddie near water, because you don't want to lose it," Essig said. "It's one of those odd situations. How many times in a tournament does Dustin throw the ball to his brother and he never drops it? And the one time it drops, it's next to water and you've got to go get it."