Looks as if there has been a shift in power with MLB’s interleague play. For years, the American League was justifiably viewed as the dominant of the two. In fact, the AL “won” 14 straight seasons from 2004 to 2017. But that streak came to an end last season when the National League posted a 158-142 record good for just shy of +10 units of profit. Thus far in 2019, the NL has maintained its upper-hand with a 77-61 +7.2 unit mark.

2019 – National League 77-61 +7.2
2018 – National League 158-142 +9.9
2017 – American League 160-140 +6.0
2016 – American League 165-135 +12.7
2015 – American League 167-133 +19.8
2014 – American League 163-137 +13.3

As with any league-wide record, we dug in to find exactly why, after over a decade, the NL was all of a sudden having success.

Last season’s interleague results were largely impacted by the AL’s bottom feeders. Four of the five worst overall records in MLB belonged to AL teams (Detroit, Chicago, Kansas City, and Baltimore). Those four teams combined for a 25-55 record in the interleague play. It was somewhat offset by the fact that Boston and Houston posted the top two interleague records (29-11 combined). Still, much of the “blame” can be traced back to the AL simply having more really bad teams.

This year’s interleague results, which currently show the NL to be 16 games over .500, once again comes down the the bottom feeders. MLB teams have played an average of eight interleague games, yet Toronto and Detroit have combined to play 28. Their combined record is 6-22! Also note that the Los Angeles Dodgers, who are arguably the best team in MLB with a 54-26 record have played a league-low four interleague games.

In looking at MLB as a whole, four of the five weakest teams reside in the AL. Toronto, Detroit, Kansas City and Baltimore are all projected to lose close to 100 games. And Seattle and Chicago are on pace to lose around 90. On the flip side the AL in on pace to own four of the top five best records in MLB.

The NL appears to have a lot more parity. With the exception of Miami and San Francisco, the rest of the NL is for the moment “trying” to win. But the NL also may only produce two or three 90+ win teams.

In the end, the NL’s recent interleague success boils down to a handful of AL has-beens basically gumming up the works rather than a seismic shift in the quality of play and teams.