Sonny Gray insists that he is healthy and his fastball velocity is as good as ever. Those two pieces suggest, until further notice, that Gray's problems are not the direct result of the dreaded "pitching hurt". Gray has also been terrible so far this season, posting a 6.19 ERA and showing little to no command of his pitches.
Is the problem as simple as "He can't locate his fastball, curve, slider or changeup right now"? Is it as simple as "He's hurt and everyone's hiding it"? Probably not. There is a third factor -- and a "shout out" goes to King Richard for bringing it up first -- that has to be in the equation. The question is where.
The third factor is that Sonny Gray, throughout 2016, has thrown his slider with about half the frequency as he did in 2015. He has thrown his changeup about twice as often. This is problematic because Gray's slider has been fantastic and his changeup has been terrible.
Inside the numbers...
Combining his various fastballs, here is the distribution of Gray's pitch selection in 2015 and so far in 2016, courtesy of Fangraphs:
2015: 64.2 fastballs, 17% sliders, 13.5% curves, 6.3% changeups
2016: 61.5 fastballs, 9.1% sliders, 16.1% curves, 13.3% changeups
Here's the problem, and it's backed up by the eyeball test that says Gray's changeup has been too close in velocity to his fastball, poorly located (often up and out over the plate), and too hittable: Gray's changeup has not been an effective pitch overall and yet he is going to it far more while abandoning a lethal slider.
Pitch values confirm this: over the course of his career, Gray's changeup comes in at +0.4 while his slider is at a whopping 18.0. Now the fastball is also an issue, having been rated a +16.3 in 2015 and a -9.9 so far in 2016. No doubt this is an essential piece, but every pitcher needs to throw his fastball a lot so if you're Gray you need to keep throwing it over 60% of the time and try to get it working for you again.
But why would a pitcher, who is struggling mightily, double the use of his worst pitch and cut in half the use of his best pitch? Last night -- and I hope you're hanging onto something firm as you read this -- 6.1% of Gray's pitches were sliders and 28.6% of his pitches were changeups.
That's insane, right? "This pitch has always been your worst one, it's not very good this year either, and you're struggling like you've never struggled in your career. Shall we throw it more than twice as much as you threw it last season? About 5 times as often as your slider?"
I have only one possible explanation, and while it might be dead wrong it's honestly the only one I can come up with. Let's look at what happened to Jesse Hahn. Hahn threw a fastball, slider, curve, and changeup, then had his season curtailed when he felt tightness in his forearm. Hahn avoided the dreaded TJS by resting and then abandoning the slider he thought might be causing the discomfort. Hahn has come back sans slider, and at least so far has been healthy as a fastball/curve/changeup pitcher.
Perhaps Gray is healthy, but only because he is not throwing the slider much. Maybe he felt something, at some point, when throwing the slider, and knowing how it played out with Hahn the team decided that Gray had better shelve the slider, throw a bunch more changeups, stay healthy and hopefully be effective with this arsenal. He hasn't been.
Why else would Gray not go to the slider more right now, when in fact he is going to it way, way less? Why would he throw nearly 30% changeups last night when last year he threw it all of 6.3% of the time on his way to a terrific season?
There has to be a reason, and as far as Encyclopedia Brown is concerned Occam's Razor (not usually Encyclopedia Brown's friend, I should note, if you read the series as a kid) says Gray isn't throwing the slider because he is not able to for some reason. And the obvious reason is that it hurts.
Do you have an explanation that makes more sense as to why Gray has been throwing his changeup twice as much this season, 4-5 times as much last night, in place of a slider that has been an extremely effective pitch for him?
Because I don't.