Surprises Among AL SP SwStk% Leaders

We all know that names like Chris Sale, Danny Salazar, and Chris Archer are going to rank among the top tier in SwStk%. So let’s instead discuss the surprising names inside the top 20 in the American League of SwStk% that have all enjoyed surges from last season.

We all figured there would be some regression in Rick Porcello’s performance this season, and while that has happened on the surface, his underlying skills have actually improved. In eight seasons heading into this year, Porcello had never posted a SwStk% above 8.7%. Here he is now with an 11.1% mark, his first venture into double digit territory. That has increased his strikeout rate, while his walk rate has remained elite.

His velocity is unchanged, but he has thrown his curve more often at the expense of his changeup. It’s not a significant change in usage, but it’s there. The odd thing is that his curve is pretty terrible at inducing swinging strikes, and inferior to his change. So that’s certainly not the explanation for the jump in SwStk%. Instead, it’s been his four-seam fastball sitting at a career high SwStk%, and a near doubling of the SwStk% of his slider. He started throwing his four-seamer higher in the zone last year, but it’s about the same this year, so that only suggests a similar SwStk% as last year, not an increase. He’s throwing his slider in the zone more frequently, which may or may not be a good thing in terms of generating whiffs. All in all, I’m not sure exactly what’s behind this spike in SwStk%.

Eduardo Rodriguez, the 24-year-old former top prospect, is actually throwing with decreased fastball velocity, and hasn’t made much of a change in pitch mix aside from throwing his changeup a bit more. And that increased changeup usage is a darn good thing, because it was whifftastic last season, and even more so this year. His fastball has also climbed into the double digits in SwStk%, though whether that’s sustainable with slightly reduced velocity is a question. It’s hard to believe he’ll sustain this level, but he’s more believable than his teammate Porcello discussed above.

Nobody fully believes in what Jason Vargas is doing, but his strikeout rate is supported by the hefty SwStk%. It’s pretty remarkable that a guy throwing 86 mph fastballs half the time could still pitch so effectively. His pitch mix is essentially the same as it’s always been, but every pitch is inducing whiffs at higher rates than before. His changeup has always been fantastic, but it’s been the most fantastic it has ever been. We don’t typically expect this from 34-year-olds. This one is hard to explain.

Alex Chamberlain discussed Nathan Karns yesterday in his excellent Small-Sample Normalization Services, which everyone should have signed up for, selecting the lifetime subscription option. Karns has also lost a bit of velocity, but he’s throwing his changeup more at the expense of his fastball, and his curve has just been incredible, generating a 27% SwStk%. Similar to how Matt Shoemaker enjoy a strikeout rate surge when he started throwing his best pitch, the splitter, more and more often, Karns has upped his curve usage literally every single game since his third outing. He has gradually taken it up from 21% all the way up to 48%! That’s crazy. I can’t believe throwing the pitch that often is sustainable, but it’s certainly working now and until hitters adjust, he should continue to induce the whiffs.

Ricky Nolasco?! While this is a jump over his marks over his previous three seasons, he’s seen this level before, back in 2009, 2010, and 2013. Nothing has changed in his pitch mix or velocity, but both his fastballs are generating higher SwStk% marks, while his infrequently used splitter is generating a career best SwStk%. This doesn’t seem sustainable, and even with a strikeout rate at its highest since 2010, he’s still nothing more than an AL-Only option that you’ll always be looking to upgrade.