Rich Hill is in the midst of a blister problem. It’s been going on since his breakout season last year. Since only three pitchers in 2016 threw more curveballs than Hill, it makes sense to blame the curve. Maybe there’s more at work, but also maybe not. It’s a pretty reasonable hypothesis.

I mean, for one, the pitcher himself believes it. “It’s right there, on the pad of my finger, where it touches the seams on my curveball,” said Hill on Tuesday night. Curious about the condition of his digit, I pushed: could I take a picture of the pad on his middle finger pad? “Nobody’s taking a picture of my finger,” he laughed. I didn’t pursue the matter any further.

But another curve-thrower obliged, so that we could have some kind of visual for our blistering analysis. Thanks to Matt Moore, we have a demonstration of where the skin meets the seams on an Uncle Charlie.

See that tension on the pad of his middle finger? How the skin is particularly white? Friction and tension — along with moisture and repetition — are the ingredients of a blister. Even though Moore throws a knuckle curve and Hill throws more of a traditional curve, the middle-finger placement is largely the same.

According to Pro Sports Transactions, last year was the biggest season on record for blisters.

Curveball use is up! Blisters are at a record high! We have created a monster! Rich Hill is to blame!

Now it’s time for the caveats. The first day-to-day mentions in the database started in 2005, so that’s a reason for a rise, first of all. And then there’s the makeup of the big years. Blisters were at a record last year, at 10 mentions. Hill himself was worth four mentions. In 2007, they were up, and it was Jeremy Bonderman who dealt with them three times. And in 2002, when they were up, it was Josh Beckett who dealt with them three times. Clearly, singular issues drive the peak years.

But we can’t dismiss that chart completely. The players who have gone down with blister problems have thrown curves 14.9% of the time, far above the 10-11% baseball as a whole averaged over that timeframe. The players who ended up on the list more than once averaged 18.9% curveballs. Enough to say there’s some smoke here.

Of course, the fire is provided by the pitcher’s own admission. Curiously, his lack of innings may be part of the problem. Brandon McCarthy showed up on the blister DL list, but he developed calluses (which he showed me) that built up over time. No problems any more. Matt Moore? Same thing: just had to build up those calluses. Even younger Giant Chris Stratton, who throws a decent amount of curves when he’s starting, felt the same: “You just gotta build up those calluses.”

Could Hill throw fewer curves to lessen the load on his middle finger? Though pitch-tracking systems don’t agree on his stuff, it seems he might be trying fewer curves in lieu of sinkers and sliders. Or perhaps not. “I don’t throw a sinker,” replied Hill when asked about it. “Just a four-seamer from the other arm slot.” And while he’s throwing a few sliders with a grip Clayton Kershaw taught him, it’s likely that many of those sliders in the system are actually curves thrown from the other arm slot, too. “It’s still mostly just two pitches, out of different arm slots,” he admitted.

So what’s left? Pickle brine, urine, or teriyaki sauce? “I’ve tried all of that stuff,” he laughed without being specific, “but rest is the only thing that works.” So he has to rest, and then throw more curveballs, and repeat until he’s got the calluses he needs. Turns out, time and repetition — the things that got him into this mess — are his only ways out.