STATE COLLEGE, Pa. -- Chris Stratton came to the Pirates in May in exchange for cash considerations to the Angels.
He then promptly injured his side, missing nearly a month. Since he's returned, however, he has been nothing short of a solid bullpen piece. He has posted a 2.55 ERA backed by a solid 3.13 FIP. He strikes out a fair number of batters -- 24.5 percent of his hitters faced since joining the PBC have punched out, a measure above the MLB rate of 23.2 percent for relievers -- and he carries a ground ball rate of 45.1 percent against a fly ball rate of 33.3 percent. Those marks are a tick better than the MLB rates of 43.1 and 35.7 percent, respectively.
Yet, Stratton's most recognizable skill lies a bit deeper than his surface numbers indicate.
Fair warning: You are about to enter the spin zone.
On curveballs, Stratton ranks in the 99th percentile of all MLB relievers with a 3,102 rpm spin rate on average. His four-seam fastball is no slouch, ranking in the 94th percentile with a 2,492 rpm spin rate. His slider joins the fun at 2,909 rpm on average.
We'll talk about the curve in a second, but let's talk about how his high-spin four-seam fastball complements his slider.
On July 23, the Pirates lost to the Cardinals 4-3. Stratton pitched from the seventh inning through the end of the game. Pretty high leverage stuff. He worked swiftly, needing just 30 pitches to get through three spotless innings while striking out four.
A couple of the Cards' plate appearances against Stratton caught my eye as they rather succinctly displayed the potential inherent in Stratton by way of his stuff.
First, he faced Paul Goldschmidt and made quick work of him:
Note: please tap or click to enlarge any graphics
Using Baseball Prospectus' matchup tool, we see that Stratton went SL-FA-SL. Note the locations of these pitches. Starting off high in the zone while coming back down to induce a ground ball, Stratton did a fine job of mixing locations.
But let's look at one key factor here:
Note the circle. These are the recognition points for Stratton's fastball and slider. They are nearly on top of each other. What this means is that Stratton tunnels his pitches very well. Simply put, this means that the pitches look the same coming out of the hand for some period of time. Practically applied, this adds deception and causes hitters to be late with getting the bat into the zone.
Let's look at it one other way, this time via Statcast:
Statcast shows a bit more separation between the two pitches, but the point is the same. With the slider and fastball arriving to the "recognition" points at nearly the same time, the hitter is on shaky ground to get a good swing off. Let's look at another example as Stratton takes on Yairo Munoz from that same contest:
And, the Statcast view:
Again, a tight grouping. Here's why all this matters. Tunneling your pitches is a fantastic idea for any pitcher. When you add similar, high spin on all of your pitches, as Stratton does, now you've got another layer of complexity, another advantage over a hitter.
A fastball with high spin tends to sink less -- and it is important to note that ALL fastballs, even four-seamers, carry some level of sink -- whereas a slider with high spin will "bite" a bit more. Stratton proves this out, as his fastball sinks 5 percent less than the average MLB rate while his slider horizontally breaks 34 percent more than the league. These figures allow him to open up the strike zone with these two pitches and get a strike anywhere he needs to:
Now, about that curveball. It's good. It's real good.
How about a 37.1 percent overall whiff rate on the pitch for starters, to say nothing of it's uniqueness. While it doesn't drop vertically all that much compared to his peers, it carries a unique horizontal quality. He can move it left or right to a such a degree that it averages 71 percent more horizontal movement than all of MLB's curveballs. It's long, it's loopy, and hitters don't like it:
Here, Kolton Wong was late to the ball, resulting in a soft ground-out, even if it took a nice pick from Josh Bell to get there.
Here's another, in which Stratton's curve is more like a slurve, and Tyler O'Neill was completely fooled:
There's a lot to like about Chris Stratton. With three distinct pitches that carry fantastic spin and movement, he has the weapons to turn into a potential late-inning reliever.
MORE MOUND VISIT
Aug 13: A sputtering offense
Aug 12: Mitch Keller’s lack of curve
Aug 6: The bullpen’s core competencies
Aug 2: Archer’s one item on his to-do list
