Park factors pitching edition

A few weeks ago I wrote about park factors and focused more on the hitters’ perspective rather than the pitchers perspective. It’s not a perfect method to predict future performance, but knowing how a ballpark plays is important to better get a grasp on a prospect at just a pure statistical level. On the other hand, pitchers are much harder to project. For instance, most people had pegged Rafael Montero as being better than Jacob deGrom, but Montero struggled in the majors and deGrom has put himself in contention for NL Rookie of the Year. Does that mean Montero is worse than we all projected him to be? Does it mean we were all under projecting deGrom? There is no correct answer to either one of those question. You could convincingly argue yes or no to each depending on how you framed your response.

Because a pitcher relies so heavily on the defense behind them, it’s a lot tougher to compare minor league park factors to major league park factors. The biggest thing a pitcher can control is the amount of HR/9 they allow. A home run is a home run, no matter what. Some parks may allow more home runs, like half of the Pacific Coast League, so if a pitcher is giving up a lot of home runs you can adjust that accordingly. Unfortunately, you can’t really quantify doubles or things of that nature, as major league scouts are duly prepared and have spray charts so they can minimize the amount of doubles they let up. Or, you could have an amazing CF like Juan Lagares, who has a ridiculous range and can run down what many can’t.

Let’s take a player like deGrom for example. In Las Vegas the last 2 seasons, he allowed just 8 home runs in 114 IP. That was in a park that allows 116 HRs for every 100 HRs allowed in an average PCL stadium, which is the 2^nd easiest park to hit a HR in the PCL. He managed to keep the ball in that stadium to the tune of .63 HR/9. That kind of statistic will translate to the major league level. It looks as deGrom has learned that it’s a lot harder to hit a HR in a major league stadium, especially Citi Field, he has gotten more comfortable and relaxed. He’s currently allowed just .54 HR/9. He’s probably not going to keep this up forever though. A HR/FB ratio of just 6.7% (MLB average around 12%) is really keeping his HR total from increasing. deGrom is not the type of pitcher who gets a lot of ground ball outs (GB% of 42.9% this year), so I would expect an increase on the amount of HRs hit closer to 12% but not that much of an increase because he does have the benefit of Citi Field. The best pitchers are the ones who can adjust to that. A decrease in walks would minimize the damage done by the long ball, the obvious reason being less base runners equals less damage.

This is really the only park factor I would look at. Many of the others are just simply out of a pitchers direct control. What they can control though, is their control. Simply put: How many strikeouts and walks do they allow? For the most part, the strike zone is pretty much the same no matter what level you play in. The stats you want to look at are K/9 and BB/9, or even better K/BB ratio. If you take a look at deGroms statistics from AAA, his K/9 was 7.3 and his BB.9 was 2.7, for a nice ratio of 2.71. Solid, but not spectacular. It would put him in the top 25 in MLB though. On the major league level, his K/9 has increased to 8.59 and his BB/9 has also increased to 3.05, but the ratio has stayed almost constant, at 2.81. This is about what you can expect. The ratio is a good translator of about what you can hopefully expect from one level to the next. Over a long period of time, you would expect these to change but you would hope to remain at or around that level to have any chance of long term success.

Let’s go back to Montero. Why didn’t he have the same level of success as deGrom? Montero has one of the most impressive K/BB ratios in all the minors, with a career 4.08. Even at AAA, he’s had some good success, with a 2.68 K/BB ratio. He didn’t allow many HRs in AAA either, which should translate quite well to Citi Field, right? Unfortunately, it looks like Montero got extremely unlucky in that respect. A 18.5 HR/FB% is extremely unlucky, but Montero didn’t exactly help himself out. His walks were up, his strikeouts were down, and his K/BB ratio dropped to an extremely poor 1.55. Was Montero rattled because he was allowing a lot more home runs than he was used to? We might never really know that answer. Unfortunately, we can’t measure confidence. He allowed 2 HR in his first MLB game. In 2013 he allowed just 6 HRs over 155 IP. Fortunately, Montero is still young and is still putting up numbers that should hopefully translate at a higher level.

Let’s wrap this up by talking about Noah Syndergaard. A lot of people have been slightly down on Syndergaard because he’s not dominating AAA like he did every other level he’s played at. His ERA is at an all-time high of 4.85. His K/9 and BB/9 would tell you to not worry about that ERA. His K/BB ratio is still an excellent 3.45 and he’s actually doing pretty good at limiting the amount of HRs hit in AAA, with just 0.88 HR/9. That’s even better than his AA numbers, where was letting up 1.33 HR/9 in a league where it’s harder to hit HRs than in Vegas. Where Syndergaard is getting hurt is the .381 BABIP the league is putting up against him. In the majors, the avg BABIP is much closer to .300. The fact is that his .380 BABIP is probably an outlier (especially considering his career BABIP is around .316) and will normalize over time. It doesn’t really help that his defense in AAA isn’t the greatest. Aside from Kirk Nieuwenhuis and Matt den Dekker, who’ve been bouncing between MLB and AAA, the defense behind him hasn’t been great. Wilmer Flores, Allan Dykstra, Daniel Muno, Zach Lutz, Josh Satin, Cesar Puello. These guys are all below average fielders at their respective positions or they are playing out of their natural position.

All these numbers and nice and all, but once again should be taken with a grain of salt. It takes a special kind of pitcher to have continued success at the MLB level. Not everyone has the kind of confidence it takes. Now, if only there was a way to measure that….