1980 MONY Tournament of Champions – A TV microphone picks up Lee Trevino talking about Tom Watson suggesting Trevino change his stance during the final round. After a viewer reports it, officials penalize Watson two strokes. Watson, who was leading the tournament, went on to win anyway.
1987 Shearson Lehman Brothers Andy Williams Open – Craig Stadler plays a shot while kneeling on a towel to avoid wet ground during the third round at Torrey Pines. After NBC showed replays of the shot during its final-round telecast the next day, several viewers called in. Officials determined that Stadler violated a rule by building a stance, and he was disqualified after finishing the final round for signing an incorrect third-round scorecard, costing him what would have been a T2 finish.
1991 Doral-Ryder Open – Paul Azinger moves a small rock with his foot while playing a shot from a water hazard during his first-round 65. A viewer reports that Azinger violated a rule that prohibits moving loose impediments in a hazard, and officials disqualify him for signing an incorrect first-round scorecard after his second round the next day.
1998 NEC World Series of Golf – Reigning U.S. Open Lee Janzen misses a birdie putt and waits while the ball hangs on the lip before dropping into the cup more than 20 seconds later. He marks a birdie on his scorecard and later signs it, but because a viewer reported Janzen’s violation of a rule stipulating that a player can wait only a reasonable amount of time to hit his next putt – 10 seconds after walking to the hole – officials disqualify him for signing an incorrect scorecard.
2010 Safeway Classic – Juli Inkster takes practice swings with a weighted “donut” training aid on her club during her second round. Officials disqualify her after a viewer informed them Inkster had violated a rule prohibiting the use of practice devices during a round. Inkster had been tied for second before being disqualified.
2013 Masters – Tiger Woods takes an improper drop after his third shot to the par-5 15th hole at Augusta National during the second round hits the flagstick and ricochets into the water. A television viewer – later revealed to be Champions Tour player David Eger, a former USGA and PGA Tour rules official – informed tournament officials, who penalized Woods two strokes the next day but did not disqualify him under a provision of the rules introduced two years earlier that allowed a player to stay in the tournament if a rules dispute arose from television evidence.
2017 ANA Inspiration – Officials penalize Lexi Thompson four strokes during the final round after a viewer informed the LPGA Thompson had improperly replaced a marked ball on the green during the third round a day earlier. Thompson, who had been leading the tournament, eventually lost in a playoff to So Yeon Ryu.