I should start with a compliment in the hopes that it will limit the amount of fruits and vegetables hurled in my general direction at the end of this post, most likely from the proprietor of #HAIL. I like Josh Satin. I think he can be a useful player on a decent major league team. He can draw a walk, and I love players who know how to work a count.
That said, I feel the need to push back against a rising tide. It has become commonplace around these parts to suggest that platooning Lucas Duda (or Ike Davis) with Josh Satin is a good solution for first base next year. The case for it goes something like this: Josh Satin had a 151 wRC+ against left-handed pitching last year. Combine that with Lucas Duda's 135 wRC+ against right-handed pitching, and the Mets basically have a top-10 first baseman next year.
Or something like that. I wish it were that simple. The purpose of this post is to pump the brakes a bit on the Satin half of this proposed platoon.
The first thing I should do is point you to this post from Fangraphs, because most of what follows is derived from there. The premise of that post is that observed performance does not equal true talent and that things—in this case platoon splits—tend to regress to the mean. At the time of the post's writing, Curtis Granderson was the poster child for platoon splits. The author uses a methodology to predict Granderson's platoon splits for the upcoming 2010 season. It is with this methodology that I will predict Satin's platoon split for the 2014 season.
You can find the specifics of the methodology in the link above, but I'll give you the nuts and bolts here. Splits for right-handed hitters are regressed against 2,200 plate appearances of league average performance. The average split for right-handed batters is 6.1% based on wOBA. This figure may have changed over the past few years, but let's roll with it for our purposes. In 2013, Satin's wOBA against left-handed pitching was .384. It was .318 against right-handed pitching, for a platoon split of 19.1%. Finally, Satin had 94 plate appearances against lefties in 2013.
When Satin's numbers are regressed, what we get is a predicted platoon split of 6.6% for 2014. Let's now take that split and apply it to Satin's wOBA Steamer projection of .318, centering the split based on percentage of plate appearances against left-handed pitching. What we get is a .306 wOBA versus right-handed pitching and a .327 wOBA versus left-handed pitching. The league average wOBA for first basemen in 2013 was .333. In handing first base to Satin against left-handed pitching, the Mets may be signing up for below average production for a first baseman.
Yes, 94 plate appearances is too small a sample, and thus it is assumed that his split will be much closer to league average than it may in fact be. However, even if you increase the plate-appearances to 1,000 versus lefties, it only brings his projected wOBA against them up to .332. That's because the biggest drag on Satin's predicted platoon split is not sample size, it's his Steamer projection. Steamer considers factors such as minor league performance, age, park effects, and many others in calculating their projections. Their prediction of a .318 wOBA is likely a result of good-not-great minor league numbers and, in the big leagues, a .379 batting average on balls in play, a .126 ISO, a 25.3% strikeout rate, and the fact that he is already 28 years old.
I would love to offer a better solution. Unfortunately, there aren't any currently in the Mets' organization. If the team is to address this need it will likely come from outside of the organization, either from the remaining free agents or a late spring training roster casualty.
Again, I like Josh Satin. His wOBA projection of .318 would have been above league average in 2013. My main issue with him is that I don't think his bat plays at first base. While Satin is not my ideal first base platoon mate, he is currently the best option to open the season there. But I suspect he will not end the season there.