Last night, Yu Darvish took the mound against the Red Sox, and not surprisingly, he racked up a lot of walks and strikeouts. This is a common trend for Darvish, who has ended 39.6% of opposing plate appearances with a walk, hit batter, or a strikeout. Darvish is the kind of pitcher who succeeds or fails on his own, relying less on his defense than just about any other pitcher in the sport.
It’s not unusual for guys with premium stuff — which Darvish definitely has — to struggle with command early in their careers. However, as Bill Petti showed back in May, normal aging curves for starting pitchers don’t show a drastic improvement in command. Is it any different with high walk, high strikeout guys who simply need to learn to harness their stuff? Or, to put it another way, have other Darvish-like starting figured out how to throw strikes and take advantage of their velocity and movement?
To look at this, I applied the new filters available on the leaderboard to restrict the list to guys who matched three variables – walk rate, strikeout rate, and fastball velocity. Since we’re relying on velocity as an input, that means we can only look back to 2002, so our sample is smaller but we’re more likely to get a better match in terms of stuff, so that’s a trade-off I’m willing to make. To come up with a list of guys who have had similar seasons to what Darvish is having now, I filtered using a minimum of 100 IP, 12% BB%, 20% K%, and FBv of 91.0 mph. While Darvish is well above the 20% strikeout mark, we do want to account for the fact that strikeout rate has been trending upwards, and so slightly lower K% in prior years were similar in terms of difference to league average. The list of names who match those inputs aren’t all that flattering.
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