Golf's 9 Most Notable Rule Changes\nWith the news that TV viewers will no longer be able to call in possible rules infractions, we look back at some of the other noteworthy rule changes in golf history.\nGolf isn't a sport where you can play defense against your opponent, but once you could. For many years in singles match play, a person wasn't allowed to move his or her ball on the green even if it was directly in an opponent's path. A player facing the obstacle while trying to hole out was known as being "stymied." They could either try to putt around an opponent's ball or putt or chip over it. There were revisions to this rule over the years before it was totally abolished worldwide in 1952.\nWhen it comes to golf balls, golfers today play a variety of brands and models -- they just don't come in all shapes and sizes anymore. Until 1974, the R&A allowed players to use a smaller ball (1.62 inches in diameter) in the British Open. In 1988, the ball was made illegal, and the USGA's 1.68 diameter model has been the only legal ball since. There has been talk about modifying the current ball to help curb distance, but nothing appears imminent at this point.\nWe take marking, lifting and cleaning our golf balls for granted these days when we're on the green, but that wasn't always the case. Take the famous playoff at Merion in 1950 when Lloyd Mangrum was penalized two strokes on the 16th hole for lifting his ball to blow a bug off it. At the time, you could only lift a ball on the green in stroke play if it was in the way of another player putting (Some PGA-run events allowed a player to do so under a local rule). In 1960, the USGA changed the rule, allowing golfers to lift and clean their balls after marking on the green -- a decade too late for Mangrum.\nThe anchoring ban isn't the first time the rules for putting methods have been altered. Golfers will try anything to improve their putting and long before long putters became en vogue, Sam Snead turned to a croquet-style stroke. The unorthodox method brought him success, but it was short-lived. Bobby Jones expressed his disapproval after Snead used it at the 1967 Masters and a little more than a month later, the USGA banned it, effective Jan. 1 the next year. "Bizarre stances and clubs were beginning to make it look like another game," then USGA Executive Director Joseph C. Dey Jr. said. Hmm. Sound familiar?\nWhen was finding a hazard even more embarrassing than it is now? When you had to drop the ball over your shoulder. In case you forgot or weren't alive, that was the procedure until 1984 (Much earlier R&A rules included dropping a ball over your head or throwing it at least six yards), when the USGA changed it to what exists now: extending the arm at shoulder height and dropping (left). Seems golf's governing body made how to drop as simple as possible -- and that's a good thing since knowing where to drop can confuse even the world's best golfers.\nIn an effort to cut down on the amount of spin a player is able to generate, the USGA changed its conforming criteria for grooves. Essentially, the edges were softened and the shape was changed (above), to eliminate the U-groove or square groove. The move was made amid growing concern that too many players were employing a "bomb and gouge" strategy since they weren't being penalized enough for having to hit their approach shots from the rough. The new rule went into affect prior to the 2010 PGA Tour season and will be enforced in amateur golf beginning in 2016.\nRemember that archaic rule that penalized players if wind or some other element beyond their control caused their ball to move on the green after they had addressed it? Actually, somehow that remained on the books until 2012. But after enough high-profile players were affected, most notably when Webb Simpson took a penalty for his ball moving before a tap-in that may have cost him the 2011 Zurich Classic (left), the USGA acted. Now, if a player addresses the ball and wind or gravity causes it to move, he plays it from the new spot with no penalty.\nGolfers anchoring long putters to their bodies is nothing new. Those golfers finding success at the highest level is a recent trend, though. Keegan Bradley became the first player to win a major doing this at the 2011 PGA Championship and Webb Simpson (2012 U.S. Open), Ernie Els (2012 British Open) and Adam Scott (2013 Masters) have followed suit, which caused golf's governing body to take a closer look at the method. This USGA rule doesn't outlaw long putters, but it prohibits players from anchoring them to their body during the stroke. "This decision gets back to the USGA and R&A feeling that fundamentally golf for 600 years has been about picking up the club, gripping it with two hands and making a free swing away from the body," USGA Executive Director Mike Davis said.\nAfter decades of golf being the only sport where people at home can affect the outcome of a tournament, that finally changed on Dec. 11, 2017. Golf's governing bodies announced that starting Jan. 1, 2018, TV viewer call-ins regarding possible rules infractions will no longer be considered. Although there had been a growing sentiment to do this for a long time, Lexi Thompson's situation at the 2017 ANA Inspiration was clearly the impetus behind the new rule. Thompson, who was comfortably leading in the final round, was assessed a four-shot penalty after someone emailed to report she had incorrectly marked her ball on the 17th green during her third round. Thompson eventually lost in a playoff to So Yeon Ryu. Video replay can still be used to review possible rules violations, but there will be designated rules officials to monitor potential issues as they arise at the tournament.