By this point, everyone is likely well aware of how Franklyn Kilome's season started for Lakewood: He was a mess. In some starts, his velocity was down, and his 15.83 ERA after his first three starts was cause for some wariness. The Phillies shut him down for one start to work through his problems and, since then, he has completely tured his season around.
For the uninitiated, Kilome's fastball usually sits in the 92-96 range while routinely touching 97. There have been unconfirmed rumors that he has touched a bit higher, and there is a chance he can add a bit more velocity as he continues to fill out, but 97 is the top of his range for now. His delivery is fairly low effort, and the velocity comes easily. He also gets a lot of natural sink on his fastball, as well good downward plane thanks to his height. Last year, the Phillies changed his slider to a curveball, and the pitch flashes plus potential while normally sitting in the high 70s or low 80s. The new curve is a power pitch that Kilome can get sharp, two-plane movement on. His changeup is still a work in progress; he has had starts where it just is not present or is too hard, lacking in good deception and movement. He has, over his career, also shown that he can find feel for a changeup with fade and velocity separation from his fastball. There is room for optimism going forward, but "work in progress" is the safest descriptor for the moment.
Two of the biggest questions entering the year for Kilome, outside of the normal concerns over workload, were (1) whether he would make improvements in his command/control and (2) whether he could strike batters out at a rate that aligned with his raw stuff. To examine this, I am going to look at BB% and K% over the course of this season. Using the percentage figures allows for a fairer and more accurate analysis, given that poor outings can inflate per-nine numbers, while unusually efficient outings can have the opposite effect.
The orange line is Kilome's individual game K%, with its partner being his individual game BB% on the yellow line. What is more encouraging is the blue and gray lines, which are the cumulative K% and BB%, respectively. As we can see, Kilome actually got his BB% under control rather quickly with a sharp drop after those first few rough starts, and he is now starting to bring it back down following his most recent starts. The K% is what impresses me, as it continues to climb over the course of the season.
Stats without context is just me shouting at you. You know I am saying something, but you are not quite sure what it actually is and whether you should care. Given that BB% and K% are less used than BB/9 and K/9, it is a bit more difficult to make the translation as to what values are Good, so let's take Kilome's season BB% of 10.1% (his BB/9 is 4.0, for reference) and find a Major League corollary. The answer is about Tyler Chatwood, with guys like Adam Conley and Yordano Ventura in the same general vicninty. It is not particularly good; certainly not disastrous, but not great. His season K% of 25.1% (K/9 of 10.1) is much more optimistic, and lines him up right now with Jake Arrieta, John Lackey, and Jon Gray. We can see that all three of those pitchers have a K/9 closer to 9 than Kilome's 10, which shows some of the deception inherent in the numbers.
Full season analysis is all well and good, but we know something changed along the way, so we can throw out the early season data in the first handful of starts for our analysis because we know it is downside, not really true talent level. If we do that, we now have a BB% of 8.9% and a K% of 27.4%. While still technically arbitrary, this is some basis for skipping past those first few starts, given the assumption of adjustment. It turns out this later stage is almost an exact alignment for Chris Archer. Archer has pitched below his talent level this year, but is still extremely talented. Kilome has kept the ball in the park more than Archer this year, but the larger point is that if Kilome can keep up what he is going right now, he is statistically similar to a lot of No. 2 starting pitchers in the majors.
Now, just for fun, let's look at Kilome's recent unsustainably hot streak over the past five games, as it shows just how far he has come this year. Over these last five starts, Kilome has a 3.5% BB% and a 35.7% K%, which is basically Jose Fernandez-level strikeout dominance (the fact that Fernandez is going that in the Majors, to boot, is just insanity). This is not a level that Kilome can sustain, but it provides a glimpse of just how much talent is there.
We now need to move away from the stat side and onto the bucket of cold water: Kilome is doing this in Low-A. There is a lot that needs to happen for him to reach his ceiling. He needs to find changeup consistency and have that pitch be at least an average pitch. Kilome, like most young arms, needs to constantly improve fastball command, because higher level hitters are not going to go down simply by putting a high velocity fastball with movement in the zone. He is also going to need to maintain the mechanical adjustments he made early in the season, because he is a big pitcher with long limbs that need to remain closely controlled. None of these are out-of-the-ordinary flaws for a pitcher of Kilome's experience level, but they are steps he will need to take. For now, he is the Phillies' top pitching prospect now that Jake Thompson is in the majors, and for me he should be on global Top 100 prospect lists this winter.
His arm is special.