Starlin Castro is currently mired in a slump. That’s no secret, as is currently sitting on a .235/.269/.327 line. To put those numbers in perspective, Castro walk rate, isolated power, and batting average, as they stand right now, are at career lows while his strikeout rate is at a career high.
As I was listening to the Fringe Average podcast today, they brought up the topic of management trying to change a hitter in the hopes of those changes manifesting in the player, therefore becoming better. Castro has been criticized, seemingly ever since he came up, for not walking enough. Under general manager Jim Hendry (who signed several free swingers), that wasn’t much of a problem. But when Theo Epstein and Jed Hoyer took over the show, it was certainly something of an issue.
What I am getting at isn’t an accusation of guilt, but an inquiry in search of an indictment. It’s next to impossible to assign blame to any one person, let alone an entire organization, without knowledge of their inner workings and what actually happened. What I want to present is a statement of facts about the Cubs’ potential superstar shortstop under the two regimes, and for you to make your own judgement based on the data supplied.
Let’s start by pointing out some things right away. First off, Starlin had more plate appearances with Hendry than he has had with Theo. Second, I hypothesized (based on data), that Starlin Castro walks more in the second half of the season than the first. He obviously hasn’t had the second second half under Theo, so take the walk rate with a grain of salt. Also worth remembering, and this is such a duh statement, Castro was older and more experienced under Theo, meaning he should naturally hit for more power and, one would hope, better in general with age.
Looking at this first set of numbers, you can see that Castro’s number really aren’t all that different between the two regimes. His line drive rate is lower than ever this year, but his other numbers are about average. The only thing really worth delving into is his ground ball to fly ball rate, which has actually improved. When it comes to Castro’s performance on balls he made contact with, he’s gotten better with age. No surprise there. This should naturally happen as he gets closer to his prime.
This box isn’t as kind. As you can see, almost every one of his numbers has gotten worse under Jed Hoyer and Theo Epstein. His batting average is 34 points lower and his walk and strikeout rates are both worse. The only thing to improve was his isolated power, which isn’t surprising given the increased strength that comes with age.
It gets worse. On June 12, 2012, it was reported that the Cubs fired Rudy Jaramillo as their hitting coach and replaced him with James Rowson. This was another decision that moved the Cubs from the Hendry regime to the Epstein/Hoyer regime. At that time, Castro was hitting .308/.320/.445. He finished 2012 at .283/.323/.430. As you can see from the below graph, Castro hasn’t seen much success since firing Jaramillo.
Castro’s average plummets another 16 points while the strikeout rate only ticks down a bit. The walk rate actually improves here, but everything else is a mess, all because of the low batting average.
It’s impossible to know what happened with Castro, but we can set two different end points and find the same results: Castro has been worse under hitting coach James Rowson than Jaramillo, and worse under Theo Epstein and Jed Hoyer than his time with Jim Hendry as general manager. I don’t want to recommend anyone getting fired as I don’t even know 1% of what is going on in the Cubs clubhouse, film room, or dugout, but the data certainly points that something has gone horribly wrong with Castro. Maybe this would have happened regardless of the general manager or hitting coach. We have no idea.
But what we think we know about the situation is that the new regime had an interest in improving the plate discipline of its hitters so they would walk more and get better pitches to hit. James Rowson was a symbolic change to that philosophy. All signs point to the Cubs tinkering with Castro’s approach and trying to get him to be more selective at the plate. This would be done with the player’s best interest in mind, but the results haven’t met the intentions thus far.
That being said, they may not have tinkered with his approach at all. Jacoby Ellsbury has never walked much, but there aren’t any signs (as far as I can tell) that Theo tinkered with his approach while he was in Boston.
The bottom line is, we have no idea. We just have data, and it says something has gone horribly wrong in the last year. At the beginning, I said I was merely looking for an indictment based on the data. I’d say there’s enough here to go to trial.