Rich Harden will try to stave off elimination Saturday night in Chavez Ravine. Harden, despite control issues, remains tough to hit. The Dodgers will counter with Hiroki Kuroda. Kuroda shut-out the Cubs earlier this season, but isn't a sure thing for the Dodgers.
Buster Olney reported (sub. req.) that he "heard" Harden had a cortisone shot in "early September." That got me thinking, how's his stuff start-to-start?
With PITCHf/x, I'll look at the relationship between Harden's fastball and change-up velocity, their movement and effectiveness. I'll use blunt instruments. Take your grain of salt and dig in.
Basic question, does a bigger difference between the two pitches correlate to effectiveness? Or is it simply the quality of the pitch itself? The answer is complicated. There are so many factors, and I'm using aggregated pitches (by start). But, to make a long story short...
The fastball basically thrives off of its own velocity. Faster fastballs yield more swings, more whiffs, and more swings out of the strike zone. The bigger the gap between the fastball and change-up speed, the more swings out of the zone, too. And more whiffs.
In other words, when Harden throws harder, he'll get more whiffs and swings out of the strike zone. Having a good separation in the change-up in terms of speed will increase the number of chases and the number of whiffs.
There is only one place where a bigger difference in movement seems to help either pitch. More whiffs on change-ups when the difference in movement is larger. The relationship is weak, however.
By these measures, Harden's effectiveness is keyed, to some degree, by the speed of his fastball. With his four-seamer, the harder he throws the more it "rises." It also separates more from the change-up and makes that pitch harder to hit.
While Rich seemed to get away with less velocity in his most recent start, this makes me doubt that's something he can continue to get away with.
In addition to the weaknesses of this method of analyzing pitches and their effectiveness (in terms of precision), there's something else to keep in mind. Harden is a very effective pitcher always. We're talking shades of good to great, no matter what. I'll take him at 90 mph over just about anyone else at 95 mph.
Here's one more blunt tool: Game Score compared to the same measurements used above. Like everything else I've looked at, their is a positive correlation. No matter what variable, it went up when any factor went up.
In general, there were plenty of instances that prove otherwise, so there is no certainty anywhere. It's a cloud, with the exception of the few items I mentioned above.
For what it's worth, Game Score doesn't correlate strongly with anything here.