The Boston Red Sox have a mostly new rotation in 2015 ‒ and one holdover. After looking in depth at his fastball and how to visualize the strike zone, Ian York has studied the data and examines his 2014 pitching repertoire of Clay Buchholz.
Having stepped through how these visualizations are created, we will look at the 2014 pitches for all five presumptive 2015 Boston starters: Clay Buchholz, Rick Porcello, Wade Miley, Joe Kelly, and Justin Masterson. To keep things manageable, a cutoff of 100 pitches was used. Although PITCHf/x is not great at identifying the specific pitch thrown, it does classify most pitches reasonably accurately, so we will use those classifications here.
(FF-Four-seamed Fastball, FC-Cut Fastball, FT-Two-seamed Fastball, CH-Changeup, CU-Curveball, FS-Split Fingered Fastball)
Buchholz was, overall, a mediocre pitcher in 2014 (ERA+ of just 72. 100 is MLB average), and it shows in these plots. All of his pitches, to both LHB and RHB, have a lot of red in them. The size of each circle represents the number of pitches that were strikes, hits, or outs in a particular sub-region; red indicates successful contact, and the deeper the red color, the more hard-hit.
In general, Buchholz does not have overpowering individual pitches and depends on location for effectiveness. That can be seen in the range of colors, from blue to red, for most of his pitches depending which sub-region they are in. For example, his two-seam fastball (“FT”) and his curve (“CU”) were both quite effective at the bottom of the strike zone, but were much less so (increasingly red) when left up in the zone. Unfortunately for Buchholz, in 2014 many of these pitches were thrown in the middle and upper part of the strike zone, where quite often they could be hit, hard.
Buchholz had moderate splits between RHB and LHB, with LHB hitting somewhat better against him, as is common for a RH pitcher. This also shows up in these charts; for example, his four-seam fastball (“FF”) and his cutter (“FC”) were at least modestly effective against RHB.
Buchholz does have a wide range of pitches that he can throw effectively. For example, here’s an animation of Buchholz, from one of his better games in 2014: Apr. 16, 2014 v. the White Sox, striking out left-handed batter Conor Gillaspie by using six different pitches in a six-pitch at-bat. As with all these charts, this is from the umpire’s viewpoint:
Buchholz has shown in the past that he can produce excellent results (as in 2010 and 2013), and his individual pitches in 2014 didn’t seem particularly different from those in 2013 in terms of velocity or movement, so it’s possible he’ll return to effectiveness if he can stay healthy in 2015.