LOS ANGELES -- No one else had to know about the extra club in Zach Nash's golf bag.
The five-wood belonged to a friend, and Zach forgot it was there as he played his way to victory in a junior tournament near his Wisconsin home this summer.
The 14-year-old accepted his medal, celebrated with grandparents who had come from Iowa to watch, and stopped by his country club to share the news. Then his golf pro noticed something amiss.
"Count your clubs," he told the teenager.
Fifteen -- one more than allowed. Zach's eyes filled with tears.
"It registered right away," he said. "I knew it was wrong."
If Zach had just won a basketball championship or a big football game and someone discovered a violation after the fact -- a technicality, really -- it would not have mattered. Bending the rules has become acceptable, if not encouraged, in much of sports.
Look at Derek Jeter, the New York Yankees' star who recently faked being hit by a pitch, wincing and grabbing his arm in mock pain, to gain first base. He later acknowledged his deceit, but no one suggested that he be punished for it.
Golf is different. In a win-at-all-costs world, the game holds itself to a higher standard, demanding that competitors know every rule and call penalties on themselves.
"Even the slightest imputation of cheating, maybe you can get away with that in other sports, but not in golf," said Steve Schlossman, a history professor at Carnegie Mellon University who chronicles the game. "That will be used against you."
For Zach, informing tournament officials about the extra club would mean returning his medal. His golf pro told him to go home, think it over.
"It was between Zach and me," Chris Wood said. "It was up to him."
As a philosophy professor and former golf coach at Hamilton College in upstate New York, Robert Simon has some ideas about the nature of the game he loves.
"You could argue that it is a very useful counterforce to the 'if you can get away with it' model that dominates other sports and other parts of society," he said.
This isn't a game where referees watch closely and assume responsibility for the rules. In golf tournaments, dozens of competitors are spread across acres of land, so officials cannot hope to see each shot.
Players also feel the weight of history. Golf dates to at least the 15th century with Scottish shepherds knocking stones about the countryside, but it became popular as a pastime for the wealthy who seemed to have stringent codes for every occasion, even when it came to shooting at each other in duels.
"This goes back to the British class structure," Simon said. "It was a sport for gentlemen, not laborers, and gentlemen did not care about winning. They cared about doing the right thing."
Honesty became a badge of honor -- rectitude nearly as important as sinking a 20-foot putt. When one of the game's early stars, Bobby Jones, was praised for calling a penalty on himself at the 1925 U.S. Open, he replied, "You might as well praise a man for not robbing a bank."
This ethic has survived into the modern era, as evidenced by the final hole of the Verizon Heritage tournament in South Carolina in April.
Brian Davis stood on a stretch of sand beside the 18th green knowing that he needed a delicate chip for the first PGA Tour victory of his career. But immediately after hitting the shot, he beckoned to a nearby official to say that his club might have ticked a loose reed on the backswing, which constitutes a violation when standing in a hazard.
The infringement was so slight, no one else would have noticed.
"I didn't feel it," he said. "It was one of those things; I thought I saw movement out of the corner of my eye."
A slow-motion television replay confirmed his suspicion. The penalty cost him a chance at the trophy and a $1-million check.
Davis told the official, "I could not have lived with myself if I had not called it."
There is a sports adage: If you're not cheating, you're not trying. Athletes and coaches call it "gamesmanship."
So, if Zach wanted an excuse to keep his mouth shut, he did not have to look far.
The Jeter incident drew scattered criticism from media and fans, but not much from within baseball. Even the other team's manager, ejected for arguing the call, later told reporters: "I thought Derek did a great job and I applaud it because I wish our guys would do the same thing."
Former USC tailback Reggie Bush elicited similar praise for a questionable play that decided the 2005 game at Notre Dame. The Trojans stood one yard short of a winning touchdown with the clock ticking down when Matt Leinart tried a quarterback sneak. The Irish defenders stood him up at the line of scrimmage, but Bush raced from behind and gave Leinart a helpful shove into the end zone.
The so-called Bush Push -- an apparent violation that drew no penalty -- ranks among the rivalry's historic moments.
"You could say Reggie pushed him, which he did," said Charlie Weis, the Notre Dame coach then. "But that's heads-up by Reggie."
Stretching the rules has become so common that athletes make it part of their repertoire, soccer players diving to the turf and basketball players flopping backward in hopes of drawing fouls.
"We all accept it," said Jan Boxill, director of the Parr Center for Ethics at the University of North Carolina and editor of an essay collection titled "Sports Ethics." "There are certain kinds of strategies that everyone has agreed to."
Golf's stubborn refusal to compromise has, over the years, prompted critics to suggest the sport is too strict.
During World War II, as German planes flew raids over London, the nearby Richmond Golf Club demanded a one-stroke penalty for any member wishing to retake an errant shot "affected by the simultaneous explosion of a bomb." Players were also asked to remove shrapnel from the fairways to prevent damage to the mowers.
As recently as this summer, a spate of curious rules and interpretations led to controversial penalties.
Dustin Johnson lost his chance at winning the PGA Championship when his ball landed in what appeared to be a patch of dirt with spectators crowded around. No one realized they were all standing in a haggard sand trap and Johnson violated a rule that prohibits a golfer from letting his club touch the sand before swinging.
Though he arguably benefited from testing the consistency of the surface, other recent violations had nothing to do with actual play.
LPGA veteran Juli Inkster was sent home for slipping a weighted "doughnut" -- an improper training device -- over her club to take a few warm-up swings during a long delay. On the men's tour, officials disqualified Jim Furyk for arriving minutes late to a promotional event before the tournament even began.
"I have no idea how the commissioner let this rule go through," tour pro Phil Mickelson said. "It's ridiculous."
But when two LPGA golfers inadvertently played each other's balls on the 18th fairway, the reaction was markedly different.
Shi Hyun Ahn and Il Mi Chung did not inform officials until after the round had ended and they had signed their scorecards. They were disqualified for not penalizing themselves at the time of the error. The situation worsened when an Internet report suggested they knew of the mix-up on the 18th green and discussed keeping quiet.
Though an LPGA investigation cleared the women of any misconduct, the mere suggestion of cheating caused a stir in the golf world.
"It got a little heated," tour spokesman David Higdon said. "Players are pretty passionate about this stuff."
The demand for honesty extends all the way down to casual play. In a television commercial, a weekend hacker surreptitiously kicks his ball into better position and Mickelson appears from behind a tree to inform him that using the "foot wedge" violates Rule 13-1.
Rickie Nash does not want anyone to think that her oldest son is a saint. Zach talks back to his parents on occasion and fights with his two younger brothers, "just like any teenager does," she said.
His love of golf began about three years ago when his Uncle Sam took him out.
Standing just over 5 feet tall with a slight build, Zach does not hit the ball especially hard but has a reliable game off the tee and an accurate putter. In a relatively short time, his handicap has dipped to five.
"He is so engrossed in the game that he'll go home and watch the Golf Channel all night," golf pro Wood said. "He is trying to absorb all this information."
Just as important, it seems, the young player has embraced the tenets of his sport, allowing older members to play through, showing unfailing courtesy around the clubhouse.
"He recognizes that this is not just about playing," Wood said. "It's about the attitude you portray."
On that August afternoon when Zach realized he had an extra club in his bag, he thought about his earliest days in golf.
"My uncle put it in my head that rules make the game what it is," he recalled. "They're so important."
But he also thought about the way he had performed, shooting a 77 to win his age group by three strokes, and the excitement of having his grandparents there. His error had no effect on the final score.
"I mean, I never used that club," he said.
The Nash family was sitting on the front porch when Zach came home, in no way resembling the proud, happy kid they had last seen accepting a first-place medal. He had decided to make the call.
A part of him wondered whether officials might choose to overlook such a minor indiscretion. But this was golf, and rules are rules. Zach packed up his medal and dropped it in the mail.
"I just knew what I had to do," he said.
It will make him a better player, he hopes. As the days have passed, reporters have called to ask questions, comparing him to Brian Davis.
"I never knew I could get so much recognition for just doing what's right," Zach said.
Then came another tournament, a chance to get back on the course and forget. Well, almost.
Before teeing off, Zach counted his clubs -- four times.