Contact and Strikeouts: The Mystery of Nick Castellanos

When the Tigers decided to swap Prince Fielder for Ian Kinsler — side note: Kinsler is already +1 WAR ahead of Fielder on the season, reinforcing just how great a deal that was for Detroit — it was done, in part, to open up a spot on the field for top prospect Nick Castellanos. Fielder’s departure meant that Miguel Cabrera could move back to first base and Castellanos could take over at the hot corner, improving their defense at both positions. And Castellanos’ minor league track record suggested he would bring some offensive upside to the table as well.

So far, he’s basically lived up to expectations. He came in to the day with a 98 wRC+, right in line with what Steamer and ZIPS forecast before the season began, and that was with a .256 BABIP; give him some positive regression on that front, and the overall package looks like a slightly above average offensive player. While Castellanos is more of a good-at-everything-great-at-nothing kind of hitter, his most positive attribute so far has been his below average strikeout rate; at just 15%, he’s striking out about 25% less than a league average hitter this season.

But while we could have expected a better-than-average strikeout rate from Castellanos based on his minor league track record, the fact that he’s striking out so rarely is actually pretty weird. Because Nick Castellanos, for the first few weeks of 2014, has the 9th lowest contact rate in all of baseball. He has about the same contact rate as Curtis Granderson and B.J. Upton. He’s making contact less often than Ryan Howard, Giancarlo Stanton, and Adam Dunn.

The relationship between contact rate and strikeout rate is very strong. Here’s a plot of the two metrics for all qualified hitters in 2013.

That is a very strong linear trend, and as you can see from the regression equation, the r squared between the two is .85, meaning that nearly everything you need to predict strikeout rate can be found by looking at contact rate. Contact rate doesn’t perfectly predict strikeout rate, but it is the dominant variable, and knowing contact rate gets you most of the way to knowing strikeout rate.

This is pretty common sense, of course. Guys who swing and miss not only are going to swing and miss at more two strike pitches, but also get to more two strike counts to begin with, since they were swinging through zero-strike and one-strike counts that higher contact hitters would have put in play, ending the at-bat before a strikeout was ever possible. It isn’t any kind of revelation to say that contact rate and strikeout rate are highly correlated.

But now, look at the same graph, only focusing on 2014 data.

Because we’re dealing with smaller samples, the plot is a lot more scattered; this will even out as the season goes on, and by the end of the year, the 2014 plot will look a lot like the 2013 plot. You’re always going to get more variance in smaller samples, so we shouldn’t be surprised that the spread is wider here.

But even with that wider variance, look at the lower left hand corner of that graph. Note the point just above the 15% K% mark, the furthest dot from the line. That’s Nick Castellanos and his 67% contact rate. To the right of him is Marcell Ozuna, who also has a very low strikeout rate relative to his contact numbers, but every other hitter in baseball who is making contact less than 70% of the time has a strikeout rate over 25%, and many of them are closer to 30%. In fact, if you use the regression equation to create an expected strikeout rate based on contact rate, Castellanos’ xK% is actually 30%; he is striking out half as often as his contact rate would suggest.

No hitter in baseball is further from their expected strikeout rate than Castellanos, in fact, no one else is even all that close. Ozuna, as mentioned, is also in the low contact/moderate strikeout group, but his 18% K%/28% xK% difference is only 10 points off the regression’s formula. Castellanos is far and away the biggest outlier when it comes to low contact and low strikeout rate.

And no, this is not sustainable. Last year, Hunter Pence had the biggest positive difference in terms of strikeouts versus expected strikeouts based on contact, and he beat the regression by six percentage points. Only eight of the 141 qualified 2013 batters diverged (in either direction) more than five percent from their expected K%. Castellanos does have the profile of a guy who will strike out less than his contact rate would suggest — aggressive hitters who swing a lot get to fewer two strike counts than guys who work the count, so their swings and misses come more often in zero-strike or one-strike counts — but something is going to give.

Of the two metrics, contact rate stabilizes quicker than strikeout rate, which probably isn’t great news for the Tigers. If Castellanos keeps swinging and missing anywhere near as often as he has been, his strikeout rate is going to spike. An uptick in BABIP may very well offset the rise in strikeout rate, and this isn’t any kind of sign that Castellanos is about to stop being a productive hitter, but he is going to stop being this kind of productive hitter. You just can’t swing and miss as often as he has been and post better-than-average strikeout rates.

For reference, are are the top five and bottom five hitters in variance from expected strikeout rate for the start of the 2014 season.

Name	PA	Contact%	xK%	K%	Difference
Nick Castellanos	59	67%	30%	15%	15%
Marcell Ozuna	89	69%	28%	18%	10%
Aramis Ramirez	90	78%	21%	11%	10%
Albert Pujols	97	82%	18%	8%	10%
Andrelton Simmons	78	88%	13%	4%	9%
—–	—–	—–	—–	—–	—–
Ruben Tejada	67	83%	17%	25%	-8%
Joe Mauer	96	82%	17%	26%	-9%
Brett Gardner	77	84%	16%	25%	-9%
Abraham Almonte	94	73%	25%	35%	-10%
Garrett Jones	90	78%	21%	33%	-12%

Count-working types like Mauer and Gardner will likely continue to post higher strikeout rates than their contact rates would suggest — at 8%, Gardner had the biggest difference of any hitter in 2013, so this isn’t new for him — and guys like Ramirez and Simmons will likely not regress all the way to their xK% because of how often they swing, but these ranges are going to come down. For hitters like Castellanos, the hope has to be the contact rate is the thing that regresses more than the strikeout rate, but something is going to have to give.