When Brooks Koepka, defending his title at the PGA Championship, walked to his second shot on the par-5 seventh at Valhalla during Thursday’s first round, he was just one under. That’s a fine start at most major championships, but with the low scoring and nine-under pace set by Xander Schauffele, Koepka needed a quick finish to stay within touch of the leaders.

He got that quick finish, thanks in part to a fortunate rules break on that second shot.

Koepka’s drive on the reachable par 5 finished in the first cut of rough, which is fairly long this week. Considering that the hole was tucked on the left side of the green over water, he likely needed to play well away from it to the middle of the green.

Yet as he took his stance, he realized he had another option.

“I actually got kind of lucky,” Koepka said after the round. “I was standing on a sprinkler head. I was in the first cut, but I was able to move it back to the fairway, which kind of helped.”

There is a popular misconception that if are you taking free relief from a sprinkler head (see Rule 16.1), then you must stay in the same “cut of grass” that you were in. In other words, if you’re in the rough, you need to drop it in the rough.

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That is not the case, as a few years ago, the USGA created the term “general area” to define any place on the course except the tee, penalty areas, bunkers or putting green. Under Rule 16.1, if your ball is in the general area and you want to take relief from a sprinkler head (defined as an immovable obstruction), then you are entitled to find the nearest point of relief in the general area and drop within one clublength.

If you are in the rough, that means you can move it into the fairway, provided you’re entitled to free relief. (It’s worth quickly noting that if you are on the fringe and wanting to take relief from a sprinkler head, you are not allowed to drop on the green, as that is not part of the general area.)

For Koepka, that difference allowed him to better control his 211-yard approach, which he got to land softly, spin and finish a couple feet away. “I was either going to hit 5-iron from the first cut or move it back two yards and hit 6-iron,” Koepka said, admitting that “Obviously not aiming there, so it’s pulled.”

Koepka converted the short eagle putt and made a lengthy birdie putt on the par-3 eighth to make a late-round charge that helped him shoot four-under 67.

Should he remain in contention on the weekend as he looks to win his sixth major, he’ll have to thank his rules knowledge for jumpstarting his week.

Main image: Michael Reaves