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Runs per game are up at Coors Field despite higher outfield walls

San Francisco Giants v Colorado Rockies Photo by Dustin Bradford/Getty Images

When the Rockies announced that they planned to raise some of the outfield fences at Coors Field in March, the response immediately turned to home run suppression. In fact, Nick Groke of The Denver Post reported that the Rockies were expressly interested in limiting homers and runs in general in making their decision. The team’s studies suggested that dingers could be limited by 5-6 percent by raising the fences in strategic spots—eight feet in right-center field and five feet in left field. In the same press release, Rockies General Manager Jeff Bridich indicated that the decision was a product of “continually evaluating” the environment where the Rockies play “with the goal to be more competitive as a result.”

Now equipped with a half-season’s worth of data, the early conclusion is that the walls have had no effect in suppressing runs. In fact, scoring is up at Coors Field through 40 games.

It was not self-evident that raising the fences was actually going to do anything to prevent runs in the first place. According to Jeff Sullivan of FanGraphs, games at Coors Field have averaged 11.3 runs per game from 2011 to 2015. If home runs were to be reduced by 5-6 percent, like the Rockies suggested the change would do, it would reduce runs per game all the way down to 11.2—not even half a run per game. The reason shouldn’t be too difficult to determine. Balls hit to these locations that would have been home runs in past seasons aren’t going to turn into outs. Instead, they’re going to turn into doubles and triples. In other words, the balls will remain in play, and they’ll still be hits.

Additionally, Coors Field hasn’t been a homer-happy place for quite some time. If the intent was to reduce runs by reducing homers, the entire project began from a faulty question. The Rockies have already done quite a bit to solve the home run question at Coors Field—they installed a humidor prior to the 2002 season to keep game balls from drying out and making them a bit less flighty.

Coors Field was a launching pad during its first seven seasons. According to Baseball-Reference’s Play Index, from 1995-2001, there were 206 “ballpark seasons,” which we can define as the 81 games a team plays at home in a given year. Ranking those seasons by home runs over the course of a single year, Coors Field has six of the top eight ballpark seasons. The outlier season was 1998, but it still ranks 28th out of 206. Coors Field became immediately less homerific with the installation of the humidor. Of the 420 ballpark seasons from 2002-2015, Coors Field’s most homer-friendly season ranks 12th; its least friendly season ranks 228th. Coors Field is still, as a whole, a nice place for home runs, but it hasn’t been extreme since the installation of the humidor.

The humidor has suppressed home runs, but it hasn’t suppressed runs. It’s the piling up of doubles, triples, and even the bloop singles that make Coors Field such a great place to hit. The year-to-year batting average on balls in play (BABIP) at Coors Field indicates this. BABIP helps answer the question, how frequently do balls hit into play land for hits at Coors Field compared to other ballparks? Coors Field regularly sits atop the BABIP rankings, and it’s one of the big reasons why it’s so friendly to hitters. Unlike home runs, this holds both for the pre-humidor as well as the current era at Coors Field.

Of the 206 ballpark seasons from 1995-2001, when Coors Field was a launching pad, it was also the place most likely for a ball in play to land for a hit. If we rank the 206 ballpark seasons for BABIP like we did for home runs, Coors Field holds the top seven spots. Significantly, not a lot has changed since. The top five BABIPs of the 420 ballpark seasons from 2002-2015, the humidor era, belong to Coors Field. The Rockies’ home park also owns nine of the top 14 seasons, and 14 of the top 52 since 2002.

Indeed, data from the first half of the 2016 season shows that there have been more runs scored at Coors Field this year. Through Saturday’s game, the 41st of 81 home games for the Rockies, there have been 13.1 runs scored per game. That’s more than a run and a half more than the runs scored per game from 2011 to 2015 cited above, which formed the basis of Sullivan’s research cited above. If the second half’s slate of games look like the first, 2016 has the chance to be the highest scoring year at Coors Field in the humidor era.

Additionally, 2016 has the chance to be have the most hits and doubles of any single season at Coors Field since 2002. There have been 5.21 doubles hit per game at Coors Field in 2016; the high in the humidor era is 4.67 doubles per game in 2004. Similarly, there have been 22.17 hits per game so far this season, whereas the current full season high is 21.88 in 2012. These are major contributors to runs scored at Coors Field, and the outfield walls do nothing to dampen them.

Not only that, but through 41 games, there have been 2.87 home runs hit per game. If that holds for the remainder of the season, it would essentially match 2002 for the most home runs per game during the era of the humidor. Hits, doubles, homers, and runs are all up so far in 2016 (triples are down, but triples are rare enough to avoid patterns). While it’s easy to look at an isolated incident, such as a Trevor Story extra base hit off of the new fences and exclaim that a home run was “stolen,” zooming out and seeing run-scoring in the aggregate tells a more complete story.

It’s also necessary to note that the home run trend is league-wide. Since the mid-point in 2015, home runs have been up to about 2002 levels. That trend has remained steady throughout the first half of 2016. It’s too seldom acknowledged that Coors Field’s extreme run scoring heyday took place during the highest league-wide run scoring environment since the 1930s. Any change made to Coors Field with an eye toward run prevention, it seems, won’t overcome trends taking place across baseball.

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That the higher walls might not suppress home runs, and the fact that they could do so without suppressing runs in general, is unlikely to be a surprise to Bridich and the Rockies’ research team. They knew that home runs are not the only thing that makes Coors Field a nightmare for pitchers, and they knew that the fences weren’t going to markedly suppress runs. But that doesn’t mean raising the fences is a pointless exercise; it means that it’s an experiment.

If the experiment with the fences has a direction, it’s a decent bet that it’s directed at Rockies pitchers. This is purely speculative, but one possibility is that the fences are designed to provide Rockies pitchers, especially young ones, with some psychological cover. This could work in two ways.

First, it’s possible that the knowledge of the raised fences might cause young pitchers to pitch a bit more freely. One long-term question regarding Coors Field has been how to “conquer it.” Perhaps the answer is for players to pitch like they would anywhere else, and maybe the higher fences will make it feel a little bit more like everywhere else. In other words, maybe it will help pitchers pitch to their strengths rather than what the ballpark might do to show their weaknesses.

Second, it’s possible that doubles and triples provide less of a ding to a pitcher’s confidence. Even though the run environment at Coors Field won’t really change, a pitcher might feel better about allowing a double instead of a home run. These sorts of feelings aren’t easy to measure, but we can ask the players what they think.

Earlier this season Jordan Lyles and Tyler Chatwood talked to me about how they learned about the wall, and what they feel about it. They both stated that the pitching staff learned about the raised walls during spring training. Bridich and other members of the Rockies front office explained the research that the team had done. In short, they attempted to sell the idea to the pitchers by appealing to reason instead of emotion.

That doesn’t mean that there wasn’t an emotional component, however. I asked both Chatwood and Lyles the same question with an obvious answer: “would you rather give up a home run or a double or triple?” “Well,” Chatwood said, “you can strand the runner” if it’s a double or a triple. “I can’t think of a situation where you would rather have a home run” instead of a double or a triple, Lyles stated.

This is true. It’s also true that a double and a triple have almost as much run value as a home run, and it’s also true that balls in play, not home runs, are what inflate offense at Coors Field. I suspect those parts were left out of the Rockies’ presentation to the pitching staff. At the same time, pitchers are probably aware of this fact intuitively, even if they don’t put it in terms of “run value.” As a result, the Rockies can do something to Coors Field that everyone knows won’t actually change the run environment, but still frame it as “helping pitchers.” After all, the pitcher “still has a fighting chance,” Chatwood stated, after allowing a double or a triple. In such an extreme hitting environment, perhaps it makes sense to alter the landscape to give pitchers that fighting chance.

Raising the outfield fences is clearly an attempt to make Coors Field a little less friendly to hitters and a little friendlier to pitchers. How it goes about doing so, however, might not be immediately obvious or felt. The first half-season of 2016 shows that runs can go up, despite the higher walls. It might end up being friendlier only on the surface and after isolated events by giving the pitcher more opportunities to prevent runs. In short, we shouldn’t think about the walls as an attempt to solve anything immediately, and certainly not runs scored at Coors Field. It might be best to consider the walls as part of an experiment with long-term aims—aims more substantial than a few feet of extra wall.