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Interleague Play Is Not Over, But Results Conclusive

We have one more week left of interleague play in the 2012 season, but to be honest, we don’t need to wait for the rest of the games to play out to realize that the American League is once again putting their dominance on full display. The AL and NL have squared off in 168 of the 252 scheduled games so far, and the whippersnappers in the American League have pounded their senior circuit brethren. The current totals: 96 wins for the AL, 72 for the NL, good for a .571 winning percentage. It isn’t just a few close games going the AL’s way either, as they’ve outscored the NL 776 to 659.

With 84 games left in interleague action, the National League would have to win 54 of them to avoid a ninth consecutive losing record against the American League. Even if the NL manages a split in the remaining games, the AL would finish with 138 wins, matching their best interleague mark since 2009, and the third best mark either league has managed since interleague play began. It’s not quite as bad as it was in 2006, when the AL went 154-98, but it’s clear that the American League is still the superior league.

A popular theory for their continuing dominance is the strength of the American League East, and particularly, the presence of the Yankees and Red Sox. Having the highest revenue team in the sport gives the AL an advantage, and the competition between Boston and New York has established a standard in that division Tampa Bay, Toronto, and Baltimore have to strive for as well. The AL East is perhaps the best example in sports of the “rising tide lifts all boats” phenomenon, as the Rays, Blue Jays, and Orioles are all forced to put together better rosters to compete against the Yankees and Red Sox, and that strength shows up when they play everyone else.

However, it’s not just the AL East destroying the NL East this year. Yes, the Yankees are 10-2 in interleague play (which includes the entirety of their current nine game winning streak) and the Orioles are 9-3, but the other three AL East squads have all gone 6-6 against the NL so far. Even if we eliminate those five teams from the discussion, that leaves the AL West and Central as a combined 59-49 (a .546 winning percentage) against the NL. Being home to the Red Sox and Yankees certainly helps, but it’s not the whole story.

In fact, the quality of the non-contenders seems to have as much to do with the AL’s dominance as the quality of the top tier teams. The also-rans in the AL — Seattle, Oakland, Minnesota, and Kansas City — each have gone 6-6 in interleague play, holding their own and not embarrassing the junior circuit. The also-rans in the NL — San Diego, Colorado, Houston, and Chicago — have combined for a 13-29 mark, led by the hapless Rockies going 1-11 against the American League so far.

Indeed, the three teams currently atop the NL divisions each have a winning record in interleague play, so the best of the NL is showing that they can hang with the American League, but once you get down to the middle and lower tier teams, the differences really begin to stand out. If you take the Nationals, Dodgers, and Reds out of the picture, the NL is 54-84, a .391 winning percentage. The good NL teams can keep up with the AL, but the mediocre NL teams are getting thumped.

So, why is the AL continually better than the NL? It’s probably not any one thing, but instead a combination of factors. Baseball is cyclical, and right now, the AL just has more talent than the NL does, but that’s not going to last forever. The NL has also had a recent funk from high revenue teams being poorly run, so teams like the Cubs and Mets just aren’t as good as they should be. The DH also gives AL teams the ability to give aging sluggers a softer landing, so they can more confidently bid on free agents like Albert Pujols and Prince Fielder. And, yes, having the Yankees helps, as they’re annually one of baseball’s best teams, and give the league a leg up in heads-up competition.

The shift could begin as soon as next year, when the Astros make the transition to the American League West. At least in the near term, it will shift a low talent roster to the AL, and that in and of itself should help the NL when they meet head to head. Of course, the Astros aren’t guaranteed to stay uncompetitive, and if they develop some more talent, that could be more of a short term shock than a long term correction. But, combined with the growing intelligence of teams like the Mets, Cubs, and Dodgers, the NL now has several high revenue teams on the rise, and as they spend their money more effectively, they should build competitive rosters on a more regular basis. My guess is that the NL will start catching up to the AL fairly soon, but early returns on interleague play show that it isn’t happening yet.