No, the American League Just Really Has Been That Much Better

By Bill

The Common Man introduced our Three Questions series yesterday, and I'll pick that up tomorrow or on Thursday.  Today, though, I wanted to address something else.

Keith Law wrote a breakdown of the top 50 free agents over the weekend. It's worth reading on its own (though Insider-only), but several commenters took issue with his rather frequent reminders that the American League is a much better league than the National.  The general idea among these objectors, apparently, is that this myth of AL superiority emanates from a kind of anti-National-League bias, and that any perceived difference in the leagues in interleague play comes from the huge advantage the American League gets in getting to use a designated hitter, like the guy on the right, in its home games.

I assume that to most of us, that sounds silly.  It sure did to me.  That the AL has outclassed the NL for many years now is pretty much common knowledge, and there's just no way at all that the AL's interleague dominance can be explained away by the DH, a player who only plays half the game (which they only get to use at all in half of those games). Still, though, at least a few of the pro-NL-equality commenters wondered aloud (well, on-screen, anyway) what the interleague numbers would look like if you took only the records from National League parks, getting rid of that DH effect.

It seemed easy enough to do, but I couldn't find that information collected anywhere. So I collected it. Took half an hour or so.  Here are my results, if you're interested.  Let's talk it out:

Since interleague play started in 1997, the American League has gone 824-930, a .470 winning percentage, while playing in National League ballparks.  That sounds good for the NL -- they won more than they lost! -- but, of course, you're supposed to win more than you lose at home.  In intraleague AL games since 1997 -- that is, AL teams playing other AL teams -- the road team is 6515-7599, a .462 winning percentage.  So in the entire misguided fourteen-year history of interleague play, the AL has done .008 better against NL teams on the road than it would expect to do on the road against teams of equal strength.  Not a huge difference, certainly, but over samples that large, it may well mean something.  It's a difference of about two and a half games over the course of a 162-game season.

It gets worse for the NL, though.  In 1997, for some reason (the first year for interleague play), the Nationals crushed the Americans in NL ballparks, winning 69 of the 107 games (a .645 winning percentage and a 104-win full-season pace).  I wouldn't want to make a habit of arbitrarily removing years that don't agree with my premise, but 1997 is obviously the least relevant year for our purposes anyway, since each successive year tells us more about who the stronger league has been lately (while becoming a bit less reliable as the sample gets smaller).  So, from 1998-2010, the AL played .477 ball against the NL in NL parks, while playing just .460 ball on the road against itself, more than double what the difference is if we incorporate 1997.

And we'll keep bringing it closer to modern day, and it'll keep getting uglier for the senior circuit.  From 2000-2010, the AL held its interleague road record steady at .477, but played worse against itself on the road (or better against itself at home), bumping the spread to 21 points (.477-.456).  Over only the last five years (2006-2010), the AL has actually played at an incredible .519 level against the NL on the road, while the intraleague road record has dropped to .446.  They've collectively played like an 84-win team in NL parks, but like just a 72-win team in AL parks that aren't theirs, about the same advantage (in wins/162) as the 2010 AL East-leading Rays had over the 2010 Blue Jays.  That's a big difference.

There was a bounce-back in 2010 -- the AL was held to a .457 winning percentage on the road after four straight years of beating up the NL at well over .500 -- but we won't know for at least a couple years now whether that represents an actual leveling of the playing field (though even in 2010, the AL was .009 better vs. the NL on the road than vs. itself) or was just a blip, like the NL's relative success in 2003-2005 apparently was.

There's a lot of year-to-year fluctuation, as you'd expect, but on the whole, and especially in recent years, American League teams have played significantly better in NL parks, without the DH, than we would expect them to play against teams with whom they were equally matched.  And remember, most AL teams will have a non-trivial investment in that DH, an investment which is almost completely useless to them in these games, so we might expect the true difference between the leagues to be even a little larger than those numbers show.

The reason for this should be pretty apparent.  No one position matters all that much over a handful of interleague games, especially a position that only plays half the game.  And that's true even when you're talking about a full-time DH against, say, Aaron Miles or Nick Stavinoha (actual 2010 Cardinal designated hitters).

What does make a difference, though, is money, and the incentive to spend that money.  If you're starting a restaurant in a small town whose only other option is McDonald's, you're probably not going to shoot for top-end, five-star gourmet cuisine.  It's just not the best use of your resources, when just being Applebee's or Denny's would still make you the class of the town.  Meanwhile, if you're moving onto a block in a swanky part of downtown that already has a Morton's Steakhouse and a Ruth's Chris, you might have to step up your game a bit.

So it is with the Yankees and Red Sox.  Teams that want a chance to break out of the AL in any given year don't have to just spend a ton of money (though that helps), but they need to be smarter and less wasteful in how they do spend it just to have a chance to compete with the behemoths.  Just like your perfectly tasty $6.99 steak and eggs dinner special won't really cut it in the downtown theatre or shopping districts, stuff that might work in the NL just doesn't fly in the AL.  The AL teams are better because in order to be competitive (or even just to avoid being a complete embarrassment -- check out what the Royals have done in interleague play vis-a-vis what the Pirates have, for instance), they need to be better than the teams in the NL need to be.

So, no, NL fans with chips on your shoulders for some reason: it's not the DH, it's the fact that your average AL squad has much better baseball players, top-to-bottom, than your average NL squad.  That's just the way it is (for now), and you're going to have to be OK with that (for now).

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