If you missed it, eventual winner Sophie Gustafson's ball began rolling on the No. 14 green after she appeared to have addressed the ball. Gustafson maintained she had not grounded the club, and therefore had not addressed the ball. The distinction was the difference between a 1-stroke penalty and play-it-as-it-lies; had LPGA rules officials believed their eyes (most who watched replays believed Gustafson did ground the club), Gustafson would have later been assessed a 2-stroke penalty for violating Rule 18-2b.
One of our Rules FAQs deals with the same rule. "If the wind moves my ball at address ..." deals with a different situation, but the same rule applies, and the application is identical.
The Rules of Golf
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