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.
Those filters return 14 seasons, but three of them belong to 2012 pitchers — Darvish, Francisco Liriano, and Edinson Volquez — which doesn’t really help us in understanding how pitchers like this develop in later years. Eliminating those three leaves us with the following 11 seasons, with Darvish’s 2012 left in for context.
You’ll note a couple of repetitive names on there, as Daniel Cabrera and Oliver Perez both had multiple seasons that fell within the bounds of this type of year, so we’re not dealing with 11 unique pitchers. However, the fact that both show up on the list more than once illustrate the fact that neither really conquered their command problems as a starter. And neither did most of the other guys on the list.
Kershaw is obviously the huge success story, as he went from a 13% BB% as a 21-year-old to a 6% BB% as a 23-year-old, and has established himself as one of the best pitchers in baseball despite early problems throwing strikes. He is what people hope for when they see a guy with bad command of good stuff.
But the rest of the list essentially serves as a cautionary tale. Zambrano had a nice career as a quality starter, but he never really got past his inability to throw strikes. He only managed to get his BB% below 9% in one season — last year, at 8.8% — but also posted his lowest K% in that same season, and his career best K/BB ratio in any year was 2.35. He had a four year stretch where he was extremely good despite mediocre walk rates, so he’s an example of how a pitcher can be effectively wild, but his command problems have stuck around for most of his career.
The rest of the list is essentially filled with guys whose command and health issues kept them from consistent production. Cabrera, Kazmir, Perez, Sanchez, Volquez, and Matsuzaka all had individual seasons where they were effective despite the walks, but none of them ever put together long stretches of success, nor did they develop into guys who could throw strikes with consistency. Whether we can learn anything from the fact that all of these guys had arm problems is still an open question — it would make logical sense that one significant mechanical issue could lead to both high walk rates and a propensity for injuries, but we don’t know enough about biomechanics to substantiate that kind of claim.
With only eight “similar” pitchers in the last 10 years, we shouldn’t be making any kind of definitive claim about whether Darvish can overcome his command problems. That said, given the Rangers investment, they probably would have rather seen a better success rate than two for eight, with only one of those two successes actually becoming a strike thrower. Unless Darvish is Kershaw 2.0, it seems like his problem finding the strike zone might not be so easily fixed.