Marlins Park still not a pitcher's park three years later

Ever since Marlins Park opened, there has been a strong reputation for the stadium stifling runs consistently. Blame it on the massive dimensions, some of the more punishing in baseball, but the reputation was that Marlins Park was too big and that the walls needed to be pushed in so t hat the team could score runs. The players have complained at times as well.

"You're going to have to make sure it stays out of your head," Stanton says of his new home park. "The first bit, you're kind of soaking it up. You're thinking maybe it's not that bad. But the more we play in it ... it's worse than we thought. Balls that you feel should go way out are barely scraping. You can still get some out, but you've got to get all of it."

The players primarily have complained of the walls being too deep and affecting home runs. And indeed Marlins Park has affected home runs. According to FanGraphs, Marlins Park was tied for the lowest home run park factor in baseball after 2013, alongside AT&T Park in San Francisco.

But after 2013, AT&T Park also held a 93 run park factor, meaning it was expected on average to produce seven percent fewer runs compared to a neutral league-average stadium. Meanwhile, Marlins Park was actually expected to produce one percent more runs after two seasons! Despite the huge decrease in home runs, somehow more runs were scored in Marlins games at Marlins Park than they were outside of the stadium.

We now have three years of data on Marlins Park, and the results are surprisingly exactly the same. For three years now, Marlins Park has been a slightly hitter-friendly stadium. The numbers still do not match the reputation.

Here are the batting lines for hitters at Marlins Park versus players at other stadiums in Marlins games since 2012.

I trust the batting line more than the runs per game (calculated as runs scored by both teams per game) at a three-year window, but you can see that the difference is very minimal. The batting average and on-base percentages between the two areas are almost exactly the same, and the only difference is in the slugging percentage. That should not surprise anyone, as we already know that Marlins Park suppresses home runs enough.

This is evident in the calculations of the individual offensive statistics.

You would be hard-pressed to point out a major difference in those numbers outside of the home runs. The slugging difference is almost entirely due to the home run suppression of the stadium, but nearly every other stat is static when moving from Marlins Park to the other places where the Fish have played. About the only other thing you can really point to is the lower strikeout rate in Marlins Park, which actually seems counterintuitive since it was long believed that south Florida had a better strikeout environment due to the local climate.

You might wonder whether the Marlins have a substantial advantage batting at home versus the opposing road teams, given that half of the data comes from Miami. That has not been the case.

Again, if there's a significant difference there, it is impossible to tell. Miami and its opponents have hit about the same at Marlins Park, with identical OBPs and near-identical slugging. The visiting teams have hit 151 homers in their plate appearances, while the Marlins have had a better home run rate with 150 homers in 500 less appearances,

The one difference you can point out thus far is that Miami's pitching staff appears to be worse in other team's parks. Here are the split hitting stats for the Marlins and opponents at other stadiums.

The Marlins hit worse on the road, at a gap that is usual for most teams going on the road. But the opposing team's hitters hit significantly better in their home parks, with a gap that was more than expected for a team going home. Part of this probably has to do with Miami facing overall better competition than themselves over the last three years. But the batting numbers for opposing teams fit the profile of a pitcher-friendly park. The hitting numbers are almost all the same, except for the home runs, which explode on the road. They did so as well for the Marlins, so it does not surprise anyone.

The only season where the Marlins experienced a significant split in their home/road numbers was in 2014, so it is possible that this split is not "real" either. But the opposing teams have consistently hit better at their homes than in Marlins Park, with a gap in OPS bigger than the .030 expected in any given season.

So what is the explanation behind the numbers? Your guess is as good as mine. I have looked up and down and not found a good reason for why the numbers are so even. The Marlins appear to be close to even at home and on the road. Opposing teams have hit better in their home parks than at Marlins Park. But the overall batting numbers are barely any different, and teams have scored more at Marlins Park. There is still little support that Marlins Park suppresses runs in a meaningful way.