In the third inning of the National League Division Play-off against the Los Angeles Dodgers last Monday night, New York Mets' catcher Travis d'Arnaud sent a two-run homer over the left field wall. Having unfurled a hit that gave his team a 6-3 lead in a crucial fixture, the 26-year-old then jogged briskly around the bases. As the Citi Field crowd went berserk at witnessing the first post-season long ball of the stadium's young life, d'Arnaud was all business, showing very little emotion. No hands in the air. Nothing.

Upon reaching the dug-out area, there were, finally, some perfunctory high-fives with team-mates but, in terms of overt displays of joy, that was it. And nobody watching thought this apparent disinterest in celebrating a seismic score in a big game the slightest bit odd. Why? Because this is baseball. As per the unwritten rules of the quaint, old pastime, players who've hit home runs must not show up the opposing pitcher by appearing to enjoy the moment too much. No, really.

Dispatching the ball into the seats may be one of the most exciting plays in the sport but strict regulations govern how the hitter must comport himself in the immediate aftermath. He may not toss his bat in triumph. He may not stand and marvel at the wondrous arc the ball creates in the sky. He may not run the bases too slowly (known colloquially as “Cadillacing”) as if savouring the feeling too much. To do any or all of the above is to somehow breach protocol, to embarrass the pitcher and to invite retribution (getting hit in the back by a 95mph fastball next time he bats).

Showing bravado

“When you pimp a home run, act selfishly, you are disrespecting the founders of the game, the guys that came before you,” Washington Nationals’ veteran

Greg Dobbs

told ESPN last year.

“When you hit a homer, flip your bat, walk ten feet toward first base and stare at the pitcher, showing bravado, you are disrespecting the other team, your team, and the name on the front of your jersey. That’s the worst thing you can do.”

Self-appointed keepers of the baseball flame regard this stuff as sacrosanct, something that separates this most pastoral of games from all others.

Nobody knows how many or how few statutes there are in the unwritten canon. That’s one of the difficulties with a code that is an oral tradition supposedly passed down through generations. The other problem is that adhering to these increasingly anachronistic principles places the sport at odds with the zeitgeist.

In the modern era, celebrating a score has become an important part of the viewing experience for the younger demographic. Kids don’t just want to see an NBA player throwing down a tomahawk dunk, they regard the dramatic chest-beating afterwards as an integral and hugely entertaining element of the show. Similarly, the wide receiver who spectacularly contorts himself to make a one-handed touchdown is expected to, at the very least, improvise some sort of modern dance routine with the ball once he rises to his feet.

Like those who deplored the advent of badge-kissing and corner-flag punching in professional soccer, baseball is the angry old man in the corner, shaking his fist at this excess showmanship, tut-tutting about hubris and pontificating about how better things used to be.

The issue is the younger fan (whom the game now seriously struggles to attract), and, whisper it, some of the younger players too, couldn’t care less about the good old days and the preservation of perceived customs. They prefer their highlight reels laced with a certain brio.

Weaned on a relentless diet of showboating and trash-talking, they struggle to comprehend a peculiar sport where one of the unwritten commandments dictates that a team with a big lead must not try too hard to score again.

This is surely the only professional game where players are encouraged to take their feet off the pedals in certain situations. If ahead by a wide margin late on (nobody is quite sure the exact figure), you are also not supposed to steal a base. If the opposing pitcher has given up two consecutive homers and is struggling, the next batter up must, out of, ahem, respect, not swing at the first pitch. To cut him some slack.

At the other end of the spectrum, if the opposing pitcher is throwing a no-hitter (one of the most rare and revered feats), you are not allowed to break it up by sneaking a cheap hit with a bunt. Imagine soccer players being warned not to score a fluky tap-in if the goalkeeper is having a stormer and you begin to understand the contradictory and illogical nature of these regulations.

Rampant abuse

Yet, pompous aficionados vouchsafe that this etiquette matters because it was invented by players for players. The men out on the diamond fashioned these ordinances over the past 100 years, they tell us piously, in order to police themselves, promote respect and ensure baseball is always played “the right way”. Like much about this sport, an admirable notion undermined just a tad by reality.

After all, these guys did a much better job monitoring the observing of arcane by-laws than they ever did combatting the rampant abuse of performance-enhancing drugs by so many of their number. Then again, maybe looking the other way is one of the unwritten rules too.