You never know when just a few moments spent tidying things up a bit can be a very costly mistake.

Most average golfers never knew such a thing might be a rules violation, while three ­veteran pros learned it the hard way. Fuzzy Zoeller, Scott Simpson and Mike Goodes each suffered a 2-stroke penalty when each player’s caddie raked a bunker at just the wrong time during the third round of the 2007 U.S. Senior Open at Whistling Straits in Wisconsin.

But no longer will this be the case. The quadrennial changes in golf rules that went into effect last Sunday include elimination of the reason why those three senior golf pros were penalized.

Goodes, a North Carolinian, landed in a greenside bunker at the 16th hole. As a courtesy to a fellow caddie, Goodes’ caddie raked another greenside bunker at No. 16 before Goodes hit his bunker shot. This was a violation of old Rule 13-4a, which stated that a golfer could not “test the condition of a hazard or any similar hazard.” Raking is considered testing the condition and anything a caddie does is considered to be done by his player.

Simpson and his fellow competitor, Jon Chaffee, landed in the same bunker on hole 14. Simpson’s son, Sean, who was his caddie, raked Chaffee’s footprints and divot in the bunker before his father hit his bunker shot. That violated the same rule.

Zoeller landed in a fairway bunker, also at No. 14. His caddie walked to the front of the bunker to see over a hill. During his return to Zoeller he raked over his footsteps. This was also a ­violation of that rule.

The United States Golf Association and the R&A Rules Limited added to their thick book of “Decisions on the Rules of Golf” in 2010, a pronouncement that allowed golfers to rake any bunker on the course “for the purpose of caring for the course” before or after a player hits a ball that is in a bunker, but only under certain circumstances.

Under the new rules changes, Rule 13-4 is changed as of Jan. 1 “to permit a player to smooth sand or soil in a hazard any time, including before playing from that hazard, provided it is for the sole purpose of caring for the course and Rule 13-2 is not breached.” Rule 13-2 prohibits improving the lie, area of intended stance, swing or line of play. This replaces the 2010 decision.

Tidying up was truly costly in the past. Why, under Rule 13-4a you could not hit a ball from one bunker to another and rake the first bunker before hitting your shot out of the second bunker. That amounted to testing a similar hazard. I imagine not too many average golfers knew that rule, since you regularly see golfers rake a bunker immediately after hitting clear of it and before going to the next bunker.

Now it is legal to do so, and you can prove it by looking in the 2012 edition of the little USGA book, “The Rules of Golf.”

Nine of the 34 playing rules of golf were tweaked or changed a bit. One of these involves a golf ball moving after the golfer has addressed the ball.

It used to be that no matter what the cause for the ball ­moving after address, the golfer was penalized one stroke and the ball had to be replaced. Now Rule 18-2b “exonerates the player from penalty if the ball moves after it has been addressed when it is known or virtually certain that he or she did not cause the ball to move.” The best example of this would be if a gust of wind blows the ball into motion.

But Jim Litvack, a retired professor of economics at Princeton and long the leading rules official of the New York Metropolitan Golf Association, said, “That golfer better damn well show me the wind was blowing leaves across the fairways and that his ball was on a green as steep and as slippery as the ninth or 18th greens at the Masters. Otherwise, he caused the ball to move when he addressed it as far as I’m concerned.”

So this change may not mean an easy out for a golfer whose ball moves upon addressing it.

The definition for what constitutes addressing the ball was also changed. From now on, a golfer has addressed the ball “by grounding his or her club immediately in front of or behind the ball regardless of whether or not he or she has taken his or her stance.” It used to be that addressing the ball meant a player had to take a stance plus ground the club except in a hazard, where only the stance meant an address. That is because you can’t ground a club in a hazard.

Now this definition change does not provide for a player addressing a ball in a hazard.

Another important change in the rules involves a golfer who is late for his or her starting time.

Rule 6-3a used to read, “The player must start at the time established by the committee.” The penalty was disqualification unless the committee allowed a golfer in a given competition to be up to five minutes late. In that case, the player would be penalized the loss of hole in match play or two strokes in stroke play.

Now Rule 6-3a says that a golfer who is five minutes or less late for the start is no longer disqualified but is penalized loss of hole in match play or two strokes in stroke play. Anyone coming more than five minutes late is still disqualified.

Golfers should get acquainted with the new rules. It may also be that most average golfers should get to know all 34 playing rules well. However, it is not easy to do this.

For instance, few golfers ever see, let alone read, the “Decisions on the Rules of Golf,” a slim-Jim book of nearly 600 pages that catalogues the many important decisions made by rules officials worldwide. The book is designed to help golfers better understand how rules are applied and interpreted. It can be purchased from the USGA in Far Hills, N.J.

Although “Decisions on the Rules of Golf” is a book intended for the millions of golfers around the world, rules officials are the only folks who regularly peruse this tome. It is hard to fault the average golfer for not being up on those “decisions” of import.

But one might criticize golfers who never take a look at or own the pocket-size “The Rules of Golf.” It is particularly important for golfers to buy one of these booklets every leap year, such as this year of 2012, because it is every fourth year that the USGA and R&A, following lengthy collaboration, come out with rules changes that are in the leap year publication.

“The Rules of Golf” contains the 34 playing rules of the game, plus guides to etiquette on a golf course, golfing definitions, rules of amateur status, specifics on design of clubs and much more.

One may purchase “The Rules of Golf” from the USGA, golf pro shops, golf stores and, for home reference, download the booklet from the Internet by going to USGA.org. There is an excellent primer in the front pages of the booklet called “A Quick Guide to the Rules of Golf” that will help refresh experienced golfers about the rules and introduce the beginner to the important rules.

In order to make golf rules uniform worldwide, The Royal and Ancient Golf Club of St. Andrews, Scotland, joined with the USGA to establish the Rules of Golf from 1952 until 2004. Then the R&A, which is a separate organization, took over the task from the ancient club.

Their little book is so important that any golfer should remember, “Don’t leave home without it.”

Gordon White served 43 years as a sports reporter for The New York Times. His email is sports@thepilot.com.