The DH Just Had Its Worst Season
An interesting thing happened last season in interleague play. The American League won 53% of the games. That’s not the interesting part. The AL has won the majority of interleague games for 14 years in a row. But while that was happening, the NL did take one step forward. The designated hitter is an AL thing, something that AL teams have to actually plan for. NL teams kind of just wing it. And yet NL designated hitters in 2017 out-hit AL designated hitters. Here’s a plot of league DH wOBA, going back to the start of interleague play just over two decades ago.
Over 21 years, NL designated hitters have out-hit AL designated hitters three times. Last year, the gap was 11 points of wOBA. In 2009, the gap was 16 points. And, in 2003, the gap was an incredible 31 points. Weird things happen, but, again, it shouldn’t be surprising that the AL is usually better here. Those teams invest in the DH position. Their DHs are used to the work. The NL just benefited from a little bit of randomness.