I miss my MLB Whip Around partner. He's out on the road covering the World Series for us while I'm in Los Angeles on studio duty. We would usually hash these things out in person and I'd almost always walk away having learned something. This time, though, it's going to have to be done via JABO's Baseball Joe.
Gabe tweeted this out on Monday night in preparation for Jake Peavy's start in Game 6 of the World Series.
If you clicked that link it brought you to this graph from Brooks Baseball, a zone profile to be more specific, of Jake Peavy in 2014. The profile plots isolated power. Take note of Peavy's numbers down in the strike zone versus up in the zone.
Scary stuff. As pitchers we are generally taught to pitch down in the strike zone and to pick our times to elevate in the zone. Your velocity generally will dictate how often you can go upstairs. The more velo, the more you can climb the ladder with confidence. Peavy isn't packing much punch these days, and conventional thinking would tell you that he needs to stay down in the zone to be successful. Gabe, using season-long data, has asked you to challenge conventional thinking.
As scary as that graph was, check out this one from Peavy's time in Boston.
He was significantly worse. The iso numbers down in the zone and middle/middle go from scary to flat-out horrifying.
As you probably know, Peavy's 20 starts in Boston weren't very memorable. He went 1-9, 4.72 ERA, 4.80 FIP, 1.43 WHIP, 1.5 HR/9, 3.3 BB/9.
One last graphic. This one plots iso for Peavy over his 15 starts with the Giants, including the postseason.
Notice anything? Check the bottom of the zone, where he pitched more frequently. He saw drastic improvement. Not coincidentally, Peavy's numbers with San Francisco were also much better. He went 7-5, 2.41 ERA, 3.38 FIP, 1.09 WHIP, 0.4 HR/9, 2.6 BB/9.
What else changed in that time for Peavy? I'm glad you asked. Use of pitches really sticks out. Once he became a member of the Giants, his two-seam fastball use dropped from 22% to 8%. Cutter use increased from 17% to 25%. Four-seam fastball, curveball and slider use also slightly went up, around 3-5% each.
Without digging much further I know this: If I'm rooting for the Giants, I want the Jake Peavy of the past 15 starts and not the Jake Peavy from his first 20. When you compare those two time periods against a zone profile plotting isolated power, you'll see the better times came when he was down. Stay there, Jake (generally).
