A Baseball Weblog

Tuesday, August 10, 2010

Quick Strasburg refresher

Stephen Strasburg will make his return to the Nationals' rotation this evening against the Marlins. The Nationals say he won't go more than 90 pitches. Before his bout with shoulder stiffness at the end of last month, he had a pretty ridiculous start to his career. In his 9 starts (spanning 54 1/3 innings), he struck out 75, walked only 15, and allowed 14 earned runs for a 2.32 ERA. His FIP and xFIP were even lower, at 1.89 and 2.15, respectively. Here is a brief reminder on his stuff, along with some pitch results.

Pitch Pitch# Pitch%

He has two kinds of fastballs (a riding four-seamer and a sinking one), a curveball, and a changeup.  They're all deadly.  The four-seam/sinker distinction isn't that clear in the data, so take it with a grain of salt.  I have the four-seamer averaging over 97 mph, and the sinker just under.  He's maxed at 100.4 mph with the four-seamer; that puts him tied (with Cardinals' reliever Mitchell Boggs) for 8th in the majors in maximum velocity, and in 3rd among starters (behind Justin Verlander and Ubaldo Jimenez).  The curveball breaks a lot and is as hard (82 mph) as many pitchers' sliders.  Likewise, his changeup (just under 90 mph) is as hard as many fastballs.  Something that's intriguing about Strasburg is that while he possesses the 100 mph fastball, he still uses over 40% offspeed pitches (25.1% curves, 16.7% changeups).
Whiffs are always fun, and with Strasburg, they're everywhere.  Here are his four pitches (again, I'm not entirely confident in the fastball classification) according to whiff rate, which in this case is swinging strikes divided by total swings.  The 2010 league averages come from an article posted on the Hardball Times by Harry Pavlidis, whose work is always first-rate.       

PitchWhiff RateLeague Whiff Rate

Strasburg's reliance on his off-speed pitches has helped him keep the ball on the ground at a solid rate. In graphical and tabular form, here is the full batted ball breakdown on the 121 Strasburg offerings that have been hit into play so far. (click for larger image)

There ya go. By the way, I'm sure I'll be posting about Strasburg A LOT in the future.

Gameday PITCHf/x data is from MLB Advanced Media; it can be easily accessed via this tool.


  1. I hope you will be posting about him a lot in the future. As you know, I saw both Kerry Wood and Mark Prior enter the league with unbelievable arms, only to quickly succumb to injury. Let's wish the new phenom a long and healthy career.

  2. Exactly. Obviously, he could get hurt at any time. That's why I don't think it's wise to make any judgments about the trajectory of his career; same with any other young pitcher. What we can do is take a look at what he has right now, and what he has right now is off-the-charts stuff that few other starters possess.