Major League Baseball’s 2018 rulebook is 169 pages long. It covers everything from the legal pitching delivery to the correct way for the umpire to shout “Play ball” to officially start the game. There’s a glossary for common terms, diagrams of the field and, of course, a few notes on pine tar usage.

Yet that’s not the totality of what’s allowed in the professional ranks. At least, not according to the players. While umpires do their best to call games based on the official rules, big leaguers police themselves with their own unwritten rules. Breaking one of these rules can result in verbal abuse from an opponent at best, an outright benches-clearing brawl at worst. at These bylaws are as notorious as they are senseless and they’ve become tougher and tougher to pin down.

Don’t worry. Yahoo Sports is here to help. Throughout the season we’ll be tracking instances of these rules being broken by doing the unthinkable — writing them down.

Follow along below:

April 1, 2018
Unwritten rule broken: Don’t bunt to beat the shift in the ninth inning during a one-hitter when you’re trailing by seven runs
Offenders: Chance Sisco, Baltimore Orioles
Victims: Jose Berrios, Minnesota Twins
Punishment: Verbal abuse from the Twins to the media after the game

April 4, 2018
Unwritten rule broken: Don’t bunt to break up a no-hitter in the fifth inning
Offenders: Andrelton Simmons, Los Angeles Angels
Victims: Corey Kluber, Cleveland Indians
Punishment: Dirty glares from Cleveland players

April 11, 2018
Unwritten rule broken: Don’t slide hard into second base during a Yankees-Red Sox series unless you want to get beaned during your next at-bat
Offenders: Tyler Austin, New York Yankees
Victims: Brock Holt, Boston Red Sox
Punishment: Bench-clearing brawl

April 20, 2018
Unwritten rule broken: Don’t attempt to steal second on a 3-0 count during the fifth inning when your team is trailing 5-0
Offenders: Tim Anderson, Chicago White Sox
Victims: Justin Verlander, Houston Astros
Punishment: Passive-aggressive taunts on the field by the pitcher

April 22, 2018
Unwritten rule broken: Don’t attempt to prevent a baserunner from stealing signs — even if the runner is much taller than you
Offenders: Javier Baez, Chicago Cubs
Victims: D.J. LeMahieu, Colorado Rockies
Punishment: Overly-sensitive denials by LeMahieu of sign stealing and finger-pointer at Baez for disrespecting the game.

April 28, 2018
Unwritten rule broken: Don’t shout expletives to yourself after hitting a leadoff home run
Offenders: Tim Anderson, Chicago White Sox
Victims: Salvador Perez, Kansas City Royals
Punishment: A stern talking to from a veteran catcher served with a side of hypocrisy.

The baseball world has plenty of thoughts on the unwritten rules, as Yahoo Sports’ experts have covered time and time again. Still, the rules exist. Players continue to break them. And punishments get doled out over 162 games. They don’t always make sense, but they seem to matter a whole lot to a bunch of players and old-timers.

Notice an unwritten rule that was broken, or have a new idea for how to punish offenders? Drop a comment below as we work through all of this together.

– – – – – –

More from Yahoo Sports:
Ohtani gets quick reality check after blazing start
Report: Brady hasn’t decided on playing in 2018
McKayla Maroney speaks out on Nassar abuse scandal
Jeff Passan: How a Twitter war may spark a much-needed MLB change