The Changes of Mike Pelfrey

At the beginning of the season, we were all prepared for Mike Pelfrey to be a potential late-inning reliever. Having pitched poorly in two consecutive years, there was no reason to expect him to be in the rotation come April 6th.

Instead, those plans went out the window when Ervin Santana was suspended for PEDs. Pelfrey was then thrusted into the starting rotation, a move that didn't please me at all. Despite that, he has actually pitched pretty well after his first outing against the Chicago White Sox.

Now, I'll have to break your hearts in stating that it's been mainly smoke and mirrors. He currently has a ..259 BABIP (career .310) so he's been extremely lucky when hitters have put the ball in play. His tidy 2.63 ERA is countered by a 4.78 FIP and 4.91 xFIP. FIP and xFIP are on the same scale as ERA, so a major league average of 3.88 tells us that Pelfrey is significantly outperforming what his secondary numbers suggest.

But, this article isn't to hate on Mike Pelfrey, as I do enough of that already. Instead, I'm taking a look at what he's changed thus far this season because it's pretty significant.

The first change has likely been caused by nothing more than time itself. That is, Pelfrey is throwing his fastball harder this year, all the way up to his pre-Tommy John surgery levels. Although he couldn't generate many strikeouts, he was always able to ramp up his fastball to the mid-90s and typically sat around 92-93 MPH. In his first Twins season back in 2013, Pelfrey was throwing around the same velocity, but it dropped last year to just over 90 MPH. Not surprisingly, Pelfrey was knocked around. This year, he's throwing the ball slightly harder than in his career, averaging just under 93 MPH.

The second change is far more significant, plus I think it's also been a bigger contributor to his early success. In the past, Pelfrey was virtually a one-pitch hurler that featured a couple other offerings purely for show. When hitters walked up to the plate, they saw 75% fastballs from Pelfrey, with the remaining 25% made up of cutters/sliders, splitters, and curveballs. In 2013 and 2014, he was throwing nearly 74% fastballs. Meanwhile, Pelfrey has whittled that number down to 66% this season.

It's not a huge change, but he's exclusively traded those fastballs for one other pitch: his splitter. Going back to his first two seasons as a Twin, that splitter was tossed only 8.5% of the time. Meanwhile, this year Pelfrey has already seen fit to feature it as 15% of his repertoire. That is a significant difference, and it's possible that the change has kept hitters a little more off-balance this year.

Finally, there has been one last change that we've seen in Pelfrey's arsenal. I already mentioned that his fastball has gained a few ticks, but he's subtracted on some other pitches. That splitter is one pitch as it's down to roughly 82 MPH from 85 MPH the past two seasons. Additionally, he's done the same with his cutter, reducing it from 86 to 83 MPH. The reduction in velocities has corresponded with some extra depth on his pitches (look above at the vertical numbers of both pitches), and it's rare to have a pitcher say that he wants less movement.

Even with his poor secondary numbers, I'd argue that these differences in Mike Pelfrey's approach are a step in the right direction. Throwing harder, with a little more separation between the hard stuff and offspeed pitches should theoretically lead to a better approach in keeping hitters off-balanced. I'd still prefer to see some more strikeouts from him, but he is still a sinkerballer that features his fastball the majority of the time. If he can keep this up for the entire season, I think we'll be able to see at least one decent season out of Pelfrey in the Kasota gold.