In today’s edition, a salary cap scandal and tennis spats.

Tennis players are fighting about ettiquette and sportsmanship at the US Open in New York. What do their conflicts reveal about the history of rules in sport?

Jonathan Jurejko reported for BBC Sport that controversies around three different tactics have bubbled up:

First, net cords: when a player’s shot catches on the cord along the top of the net but still makes it across, usually out of reach of the opponent, the polite thing to do is for the player that won the point to raise a hand in apology. Julia Townsend did not apologize after a net cord went her way in a match with Jelena Ostapenka, which led to an argument after Townsend clinched her victory. According to Townsend, Ostapenka said she had “no education, no class, and to see what happens if we play each other outside of the US.”

Next, underarm serves: Since tossing the ball over your head to serve is the standard, an short underarm serve can surprise your opponent, who may not be positioned well enough to make it to the ball in time. Daniel Altmaier used an underarm serve in his match against Stephanos Tsitsipas, which really pissed him off.

Finally, body shots: literally just hitting the ball directly at your opponent. Tsitsipas beaned Altmaier in retaliation for the underarm serve.

Who here is in the right? Who has the authority to define and enforce unwritten rules?

Unwritten rules are a part of every sport. No matter how closely you study the official rulebook, you will never fully understand the game without watching or participating yourself. It’s the difference between a dictionary and casual slang. Sociologist George Herbert Mead calls this idea symbolic interactionism. Humans, he says, continuously create and recreate the meanings of things through our social interactions.

Even if we assume that at one point, all of tennis was captured in the rulebook, or all of English was in the dictionary, both became at least a little obsolete as soon as they were finished. Culture is alive, it never stops growing and changing.

But do the written rules of sport actually aspire to be as comprehensive and all-consuming as the dictionary?

For a quick history of sport rules we can look to Norbert Elias, the founder of figurational sociology, who coined the term ‘sportization’ as a way to describe the standardization and codification of rule sets that took place during the 18th and 19th century. These rules aimed to strike “a flexible balance…between the possibility of obtaining a high level of pleasurable combat or contest-tension and what was regarded as reasonable protection against the chances of injury,” writes Eric Dunning in his chapter on Elias in Theory, Sport & Society, the main source for this section.

During the medieval era, sports were relatively informal. People communicated rules orally, and locations and numbers of players varied. But by the 1700s, the first wave or sportization took place in the UK, and boxing, cricket, fox-hunting, and horse-racing began to take standardized shape. These sports were largely practiced by aristocrats, who were simultaneously developing an imperial bureaucracy. As they legislated in parliament, they began to legislate their leisure time as well.

The second wave of sportization, including soccer, rugby, tennis, hockey, athletics, rowing, and swimming, came out of the ‘public school games cult’ of the 1800s and quickly spread through the bourgeoisie and middle class. Sports prowess was prized at the prestigious boarding schools schools that wealthy boys attended and seen as a way of building good moral character. Rugby was the first school to write down the rules for their game in 1845, which included standardized locations, match durations, numbers of players, and carrying the ball using your hands. Two years later, Eton followed, disallowing hands on the ball and officially bifurcating rugby and football.

So we can see how sport emerged as social games based on customs and traditions accumulated over time. As the games’ complexities grew, and as government and industrial bureaucracy grew in scope, sports rule sets were standardized and written down. But just because they were written down at that point doesn’t mean the culture of these sports stopped growing and changing, built piece by piece through social interactions. This cumulative edifice, the magnitude of the iceberg that remains invisible from the surface, is the unwritten rules.

Unwritten rules can vary based on location or culture.

“I don’t think it was a big faux pas on Taylor’s part, said former tennis pro Chandra Rubin as a live analyst for BBC Radio 5, “even if you just consider common courtesy.” Jurejko concludes that net cords just aren’t that big of a deal in America. If players come out of different training systems, their understandings of the contours of unwritten rules are often different.

This is also clearly visible in location-based playstyles. When Canada and the USSR faced off in the 1972 ice hockey Summit Series, the Soviets emphasized teamwork and speed while the Canadians had assembled a roster of hard hitting all-stars. The press on each side accused the other of unsportsmanlike conduct based on shamateurism that cheated the rules of international sport, or violent play aimed at producing spectacle for profit. The amateur and professional ecosystems had diverged over the decades since the USSR had entered post-war sporting culture.

Please excuse a small diversion.

Speaking of the amateur-professional dichotomy (and when am I ever not), it is very interesting to look at what motivates improper or controversial conduct in sports and how we talk about it. In a low-stakes game between friends, your desire to preserve your close relationship can presumably motivate you to make nice and keep up the good mood. But when your livelihood depends on your results, you have much more substantial motive to win, and you’ll do whatever it takes.

This logic is how Soviet critics painted professional Canadian ice hockey players. They needed to play rough and fight each other because that’s what the crowds wanted, and the crowds paid their bills. The flipside is also why many British members of parliament were so aggressively pro-amateur.

Amateurism was more than just not being paid, it was “a transcendent moral principle—something to contrast the allegedly ‘corrupting’ influences in sport of financial of bureaucratic rationality,” Richard Grudeau writes. Referring to someone as a professional, on the other hand, had a negative connotation. In a House of Lords Speech in 1968, the Lord Bishop of Chester described retrospectively that, “the professional was suspect because he made money out of sporting activities. Therefore, he was regarded as a rather lower being than the amateur who played games for the purity and love of that particular sport.”

Things have certainly changed since the era of the amateur. Professional competition is unquestionably viewed as the highest level of sport played worldwide and as such, our language has changed to match. Whereas referring to a British sportsman as acting ‘professionally’ in the early 1900s would have elicited outrage, professionalism today is a behavioral standard to which athletes aspire and being called an amateur is an insult.

But back to the point of unwritten rules.

How can players navigate this? Should they really be expected to remember all the cultural nuances of their sport? Luckily, there is plenty of documentation of unwritten rules across many kinds of sport. The most frequently discussed are in baseball, to the point where the topic has its own Wikipedia page.

In terms of American tennis, though, one needn’t look any further than the United States Tennis Association itself, which publishes The Code as part of its rules and regulations. Though it admits in its preamble that “no system of rules will cover every specific problem or situation,” the PDF document aims to be “a summary of procedures and unwritten rules that custom and tradition dictate all players should follow.” It should be good enough to cover the basics, right?

Sadly, the document does not address net cords, underhand serves, or body shots.

Kawhi Leonard was (allegedly) promised $28 million in under-the-table payments from a fraudulent tree planting company so that the LA Clippers could circumvent the NBA salary cap.

While other celebrity partners appeared in commercials or other promotions, Leonard never did, yet was still receiving $7 million per year from Aspiration Partners, journalist Pablo Torre reports.

How did he find this out? He went digging after Kawhi was listed as a creditor in documents made public during the company’s bankruptcy proceedings. Why did they go bankrupt? Because their co-founder and former board member Joseph Neal Sanberg, a so-called “anti-poverty activist,” was charged with and plead guilty to two counts of wire fraud.

Is it wild to think that this company might have also been funneling secret money to a basketball star? The financial ties are certainly there. Clippers owner Steven Ballman (great NBA owner name, by the way) had invested $50 million in Aspiration, and the annual payments, for no visible work, ran exactly the length of Leonard’s contract extension with the Clippers, and brought his raise to a nice, even $10 million.

The Clippers deny this, obviously.

But sports have a long and rich history of under-the-table payments. In the 19th and a good chunk of the 20th century, most international sport was amateur only. However, as the level of competition increased, athletes needed to train full-time to keep up, meaning that those who didn’t come from wealthy or aristocratic backgrounds had little choice but to take dirty money. Long before the formation of the NCAA, universities were already providing tuition, room and board, and even straight-up cash for their athletic recruits. At the first modern Olympic Games, Athens 1896, the marathon winner received many material rewards and even a few marriage proposals for his win, despite all athletes supposedly being amateurs.

With amateur regulations gone, systems like the salary cap allow some freedom while trying to regulate athletic markets to provide parity between teams and suppress player compensation rates. This has somewhat allowed high-level sport to shake off its reputation for shady business and corruption. So I say cheers to the Clippers for keeping the old traditions of the sporting world alive. Next thing you know they’ll be bribing the commissioner to rig the draft lottery. I hope they conspire to lose the championship, if they ever do get there.