The gap between expected performance and actual performance from Hutchison has been so large that it's reasonable to assume that multiple factors have played a role. Luck, obviously, has played some role. A problem pitching from the stretch has been looked at by MjwW and is very likely a part of the disappointment that has been Hutchison's 2015. Over at Fangraphs they've pointed out that his improved slider from late in the 2014 season has not carried over to 2015. But in that same piece, Hutchison is quoted as saying that he cares more about fastball command than about the depth of his slider.
I've decided to take an in-depth look at Hutchison's fastball command. Fastball command is a tricky thing, however. Obviously you don't want too many in the middle of the strike zone, but other than that it's unclear how exactly you look for good command. Unlike with changeups and sliders (keep the low all the time), it's not clear what the best location to put a four-seam fastball is. Up at the letters has value, as you can get whiffs that way. Down in the strikezone can be very beneficial, as you can get called strikes more easily there. Pitching outside or inside can be very beneficial to getting weak contact on swings at fastballs outside the strikezone, and especially to lefties getting the "lefty strike" on the outside of the zone is a pitcher's favorite.
To get a good feel for what good command looks like, I thought I'd find some pitchers who are somewhat like Hutchison and are getting good results on their fastballs, and don't get too much value from offspeed pitches. Using pitch values to determine which pitchers are relatively good at the whole fastball thing, I'm crossing pitchers like Hector Santiago off the list for being a left-hander, Chris Tillman for having an over the top delivery rather than a lowish arm slot like Hutchison. Shelby Miller gets crossed off the list for throwing much harder than Drew, same as Gerrit Cole and Andrew Cashner.
In the end, here's the fastballs we'll be looking at:
data from Brooksbaseball.net
I put an asterisk next to the "Whiff" category, because instead of using regular whiff/swing I used the whiff/swing on pitches in the middle of the zone in an attempt to eliminate command from the equation; it suggests that Hutchison would probably have the best fastball if command didn't matter (but of course, it very much does). Another thing to note is that while Vogelsong's four-seam gets an awesome .282 BABIP, his two-seamer has had less inspiring results with a .324 BABIP (but slightly lower ISO). The same effect applies to Lynn, but not to Hutchison, whose two-seamer's career numbers have simply been awful.
Now, Hutchison's number of strikes on the fastball has been quite good (33 Ball% is almost what I'd call elite), but another part of command is where in (or near) the strikezone you get those strikes. Where have these pitches been putting their fastballs?
data from Brooksbaseball.net
With the exception of Lower 3rd%, this is about pitches outside of the strikezone. One thing to note is that Vogelsong leaves the outside pitches to lefties and the inside pitches to righties to his two-seamer. Ian Kennedy is probably the only one to challenge righties inside with his four-seamer because his four-seamer has incredible arm side movement (running into right-handers and away from lefties).
This data suggests that while Hutch has overpowered batters with high fastballs, and been decent at getting strikes low in the zone, his horizontal placement has been lacking a lot. Perhaps it's obvious, but I'm still going to use the following graph to illustrate how important location is to not getting hit hard:
For my part, I don't mind the high fastballs much. I think the "pitchers need to keep the ball down" is often overblown (Lance Lynn seems to agree), and especially in Hutch's case the narrative needs to switch to "he needs to keep the ball away". I wouldn't mind if he pitches inside a bit more, either. His fastball is hard (and deceptive?) enough that he can do that, in my opinion. In any case, if he doesn't improve the command of his other pitches, his fastball location needs to be better, period.
If you've enjoyed reading this and would like a follow-up to this article, please let me know what you'd like me to look at next. Deception? Delivery? Offspeed command? Pitch mix and/or predictability?