If I told you that as of Saturday’s games, every currently healthy pitcher in baseball with an xFIP of 3.00 or below was 100% owned, you probably wouldn’t be at all surprised by that statement. However, if I told you that of the eight eligible players for that designation, one of them was actually only owned in fewer than 25% of leagues–SPIT TAKE INTO THE COMPUTER. On one hand, xFIP isn’t a fantasy category unless you play in some hipster sabermetric league. But on the other hand, xFIP is indicative of skills which are very fantasy relevant, and a player who has been so adept at those underlying skills.

The mere fact that Rick Porcello is showing this level of controllable skills is pretty shocking given his past few seasons of performance, but not his amateur pedigree. Porcello was the 27th overall pick in the 2007 draft, but his position is misleading–he was widely believed to be the best prep pitcher available available in the draft at the time, and fell due to signability issues. In fact, to give you a sense of how highly thought of Porcello was around the time of the draft, here’s an excerpt from his scouting report from Baseball America prior to the 2008 season:

“Porcello could be another Justin Verlander in the making. His clean, repeatable delivery resembles Verlander’s, and his power stuff is also reminiscent of the Tigers ace. Porcello’s fastball rides up on righthanders and sits at 94-97 mph. He’s able to keep that velocity deep into games. He throws two breaking balls, a power slider in the low 80s and a big-breaking curveball at 70-74 mph. He also shows good arm speed on his promising changeup…The Tigers are looking forward to the day when they can pitch Porcello and Verlander in the same big league rotation, giving them two youngsters with filthy stuff.”

Yep, we’re talking about the same guy. How quickly we forget. Unfortunately for Porcello, he didn’t quite become half of the two-headed Detroit rotation with Justin Verlander. However, this year he’s shown some real improvement in a couple of different areas, but for fantasy purposes, the most exciting of which is the jump in strikeout rate. And when a strikeout rate jumps like Porcello’s has (he’s never been above a 14% K-rate until this year’s 20.4%) there are two things I tend to look at to see why: velocity and pitch selection. For Porcello, the velocity isn’t super interesting as he threw nearly a full MPH faster last year.

It’s the pitch selection where things get more interesting. The first big thing that you notice is that he’s gone from relying on his slider as his primary breaking ball to his curveball. In fact, he’s already thrown more curveballs in 2013 than the two previous years combined while the slider is being used at about 25% of his career rate. Of course, none of that matters unless the curveball has been effective, but judging by the .143 AVG and .257 SLG he’s allowed on the pitch, I’d say it has been. On top of that, his 64% ground ball rate on the curve has been a help in raising his ground ball rate to a career high of 55.7%.

The second piece is the increase in the use of his changeup, and that hasn’t been a one-year thing. Since 2010, Porcello has increased both the number of off-speed pitches he’s thrown and the whiff rate he’s gotten on those off-speed pitches. Here’s a chart showing that:

It doesn’t take a rocket scientist to see that this improvement in quality and quantity of Porcello’s change has been a big factor in the jump in his strikeout rate.

With all that said, the reason why this improvement is “hiding in plain sight” is that despite all of steps forward in his underlying skills, Porcello is still only the 86th ranked starting pitchers for fantasy purposes. Of course, that’s not shocking when you see some of his overall numbers (4.74 ERA, four wins). But beneath the surface, Porcello is managing to complete the holy trinity of pitching–7.5 K/9, 1.5 BB/9, 55.7% GB rate–while seeing his raw numbers suffer due to abnormally high home run and strand rates. His HR/FB percentage is sitting at 17.9%, while his career mark is 11.8% and his strand rate is around 4.5 percentage points lower than his career mark (64.5% vs 68.9%).

In the end, the fact that there are still questions as to how good Porcello actually is right now should tell you a lot about how much his value is in question going forward. He is a guy who has underperformed his xFIP every year of his career, so just because he has the underlying skills of someone with a 3.00 ERA, doesn’t mean that should be the expectation going forward. How much of that is embedded in Porcello’s skill set and how much of that can be attributed to the below average Detroit defense is up for debate. The cost to deal for Porcello is likely very small and could be a stealth investment at this point to see whether he can sustain a true skill level close to what he’s doing now. We’re well past the point of small sample sizes, so what he’s done is real–it’s just a matter of whether it is sustainable.

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