Which team is the Royals' biggest rival?

The Boston Red Sox and the New York Yankees.  The Chicago Cubs and the St. Louis Cardinals.  Michigan and Ohio State.  The Baltimore Ravens and the Pittsburgh Steelers.  Coke and Pepsi. These are just a few of the well-known rivalries in the sports world, rivarlies which attract significant national attention.  Rivalries exist for most teams, actually, even if the national media does not focus on them.  Really, though, you only hear the word 'rivalry' in a sports context anymore.  Stetson and Valerie from marketing do not have a 'rivalry.' They're probably just bored and don't like how the other one pronounces the word 'Missouri' (note: it is Missouree, not Missouruh).

Regardless, let us turn to the Cambridge English Dictionary for a definition. Why not the Oxford English Dictionary, you say? Well, I studied at Cambridge, and using the Oxford English Dictionary would be using the rival school's resource.  This is a real world example of rivalry that you get for free. You are welcome. The official definition:

• rival, noun: a person, group, or organization competing with others for the same thing or in the same area
• rival, verb: to equal or be as good as

The question looms: who are the main rivals of the Royals? The Bowser to our Mario? The Dr. Pepper to our weight loss convention?  For years, the Royals didn't really have any rivals.  This is what happens when you are a terrible, horrible, no-good very bad team for decades at a time.  Beating the Royals was kind of like beating your six year-old nephew at Battleship; you want to have fun, but you can't help but destroy him if he insists on clumping his ships together in the middle. It's not your fault he has only had a few dozen months of brain development outside the womb. It probably is your fault if you take glee in seeing his fallen expression after you beat him for the fourth time in a row. If this is reminding you of how Cardinals fans treat Cubs fans, then you are correct.

See, the verb form of rival suggests that teams be of roughly equal skill level.  I suppose two bad teams could be rivals, but those types of relationships are the Star Wars Prequels of rivalry; though they're technically the same as the others, they're a whole lot worse, not that fun to watch, and leave you wondering what the purpose of it all is.  Now, two good teams--that's a rivalry.  The Royals are now what we would call a Good Team, having advanced to the World Series last year and owning the best run differential in Major League Baseball this year.  They've scuffled with opponents this year and are finally a team worth caring about. So who is it? Who is the Royals' biggest rival?

Detroit Tigers

The case for: Detroit destroyed Kansas City in their season series last year, and has generally dominated the Royals in recent memory.  The Tigers have also won the American League Central outright for four years in a row.  This year, the Tigers and Royals will probably butt heads again; early standings indicate a two-horse race for the pennant, though there is plenty of time left.  Tigers are also vicious animals, along with lions and bears.  They could probably eat royalty, although the jury is still out on whether or not Slugerrr is a suitable foe for a tiger.  He's got a crown for a head, I guess. Has to count for something.

The case against: Not much, really.  It seems to be a perfect, built-in rivalry: competitive clubs within the same division trying to nab a free ticket to the American League Divisional Series year after year. I suppose, if anything, there isn't any bad blood between the two clubs.  I don't know a lot of people who just hate the Tigers, and the teams seem to have mutual respect for one another.

Also, I mean, can you be a rival with a team that boasted this as a logo once?

HELLO I AM FROM DETROIT

San Fransisco Giants

The case for: The Kansas City Royals made the 2014 World Series. Crazy, I know, and if I hadn't seen it myself I would ask you to pinch me due to fear of dreaming. The San Fransisco Giants were the opponents.  They were the black and orange menace.  And, though it makes me sad, the Giants beat the Royals in an epic, heartbreaking 7-game set.

The case against:  Before October 2014, when was the last time you thought about the Giants in a context that involved Kansas City? It probably was the last time you thought about former Royal Gregor Blanco's epic catch to preserve Matt Cain's perfect game* in 2012.

*Speaking of former Royals and perfect games, I think it's important to note that PHILLIP HUMBER threw a perfect game. Yes, the same Humber who pitched 21 innings for the 2010 Royals, a dreadful team. Pedro Martinez, Roger Clemens, Greg Maddux, John Smoltz, and Tom Glavine do not have perfect games. Phillip Humber does.  The baseball gods have some major explaining to do.

Oakland Athletics

The case for: Oakland and Kansas City go way back.  There is the fact that the Oakland A's used to be the Kansas City A's.  There is also the fact that the Athletics and Royals fought tooth and nail back in the 70s/80s, the Royals' great heyday.  There is also this

And this

And this

Frankly, the animosity between the Athletics and the Royals has been extremely exciting.  We're seeing the birth of a real rivalry here, and it's almost certain to continue in Oakland.

The case against: Oakland isn't a divisional foe.  They're not even remotely regional.  We don't run into A's fans anywhere here in the Kansas City metro.  Well, nobody really runs into A's fans anywhere, but we'll let that slide, unlike Brett Lawrie.

St. Louis Cardinals

The case for: The Cardinals are the team just on the other side of the state, a mere few hours drive from Kauffman Stadium.  Not only that, but the Royals accrued their one and only World Series victory against the Cardinals.  Then there's the whole Best Fans in Baseball thing, the whole St. Louis food thing, the whole 'where do you go to high school' thing.

Actually, I'm going to linger there for a moment.  I was with a friend in Pompeii (yes, that Pompeii) and we met another American waiting for the train back to Naples.  This man was from St. Louis, and he asked us a few cursory things. We told him we were studying that year in England, that we had a few weeks of vacation between terms, that we were both from Kansas City. Here is a list of things acceptable to then ask a stranger provided this information:

• Nothing
• Do you like studying abroad?
  
• How about those Royals/Cardinals/Chiefs/Rams/etc?
• Isn't it weird that there is a cafeteria immediately across centuries-old ruins?
• Do you guys hear that rumbling?
• Where is the nearest Taco Bell?
• Which one of you has the highest bone density?

Instead, this stranger asked us both where we went to high school. This is 2 minutes into a conversation in a country thousands of miles away from the homeland between a man with little geographical knowledge of the Kansas City area.  Maybe someday on my deathbed I'll wake up and understand everything--'BY JOVE, THAT WAS CODE!' But for now, I just despise St. Louis a little more. I think Kansas City does, too.

The case against: The Royals and Cardinals play each other only 4 games a year.  Unless they meet in the World Series soon, the rivalry is derived entirely from regional proximity and past clashes.

New York Yankees

The case for: They're the New York Yankees. Everybody hates the Yankees.

The case against: When was the last time the Yankees and the Royals had a meaningful interaction? Also, what is the probability that your average New Yorker knows the Royals play in Missouri?

Other

The case for: The Indians and White Sox have legitimate claims to be rivals, I suppose.

The case against: You can't be rivals with everybody.

OR CAN YOU?