Rattling the SABR – How Good Will Kershaw Be?
Posted by Rob McQuown on Sunday, November 1, 2009 at 5:13 am
Recently, I was involved in a discussion on a Strat-O-Matic forum, centering around Clayton Kershaw. The starting comment which got me involved in the discussion was an implication that he hadn’t “arrived”. I succinctly noted that I thought he had “arrived”. The position seemed to be that many people believe that Kershaw will get better, much better. This centers around 3 facts: a) he’s young, very young; b) his walk rate is higher than you’d like in an “ace” pitcher, and pitchers improve their walk rates; c) he doesn’t pitch deep into games, limiting his number of innings (partly due to a sane amount of caution with a young arm, and partly due to the walks).
Kershaw is young, very young:
From an MLB perspective, this helps the Dodgers, as he’s under team control for at least another 4 seasons at a nice price. For fantasy/sim purposes, many (probably almost all) owners tend to extrapolate this thinking to: “If he’s 21 now, he should improve and also give me another 15 years, which makes him 3 times as valuable as a 31-year-old pitcher, who might only have 5 more years, and those in decline.” Underlying this logic are two presumptions:
- Pitchers improve, and very young pitchers improve a LOT. \
- A pitcher’s “effective expiration date” is strongly related to birth dates.
Now, both (1) and (2) are very much true for batters. It’s true statistically for the batting population, and the level of certainty that any specific batter follows both those principles is very high. But for pitchers? Not so much. Pitchers improve by fits and starts, sort of like teenagers growing. As we all know kids who are almost their full eventual height entering high school, so we have seen many pitchers who don’t improve much – if at all – after a strong beginning. The second point is almost so absurd as to not warrant mention. How many pitchers pitch their entire career without a serious injury derailing them? And how much impact does age-related decline have for healthy pitchers? The answers to both are “almost none”.
toTo give some examples of the concept of “being almost fully grown” in a young pitcher, Kershaw posted a 149 ERA+, and here is a list of the other 14 pitcher seasons by a 21-year-old with 100+ innings and an ERA+ of 140 or better (thanks to baseball-reference.com and their P-I tool):
- Vida Blue – topped out at 142 at age 26, career ERA+ of 108
- Jim Nash – who? topped out at 123 at age 23, career ERA+ of 97
- Smoky Joe Wood – Wood had one of the best fastballs in baseball history, comparable to that of his contemporary Walter Johnson. In 1912 Johnson said, “Can I throw harder than Joe Wood? Listen, my friend, there’s no man alive can throw harder than Smoky Joe Wood.” … broke his thumb, and his career as a pitcher was done at age 25.
- Hal Newhouser – A fellow reader on the Strat blog notes that wikipedia.com has information on why he was pitching during WWII: “As World War II got under way, the Tigers moved up in the standings because several of their top players, including Newhouser, were classified as 4-F (ineligible to the drafted). Newhouser was 4-F due to a leaky heart valve; he attempted to join the service anyway but was turned down several times.” He posted a 145 at age 27 after the war, in addition to 3 stellar seasons during it (which don’t fully count, IMO). His 130 career ERA+ would likely be about 115 without the war years included.
- Bob Feller – HOF pitcher, topped out at 153 ERA+ at age 27, next-best was a 130.
- Mark Fidrych – lucky for Clayton, he didn’t arrive in THAT era of frequent pitching abuse.
- Babe Ruth.
- Jose Rosado – topped out at 130 at age 26, career ERA+ of 114, not sure why he was done after his age-25 season.
- Ralph Branca – His age-21 season came during WWII, so his career ERA+ of 104 isn’t a surprise.
- Whitey Ford – didn’t pitch at ages 22 or 23, came back to pitch like the HOF-er he became (133 career ERA+).
- Brett Saberhagen – topped out at 180 at age 25, career ERA+ of 126, historically large variances.
- Eppa Rixey – Never topped his 144 ERA+ at age 21 again (though he had 144, 143, and 142 seasons at ages 41,25,34 respectively), nice durability, career ERA+ of 115, Bert Blyleven isn’t in the HOF, and this guy is?!
- Britt Burns – topped out at 136 at age 22, 111 career ERA+
- Bill Stafford – topped out at 136 at age 24, 103 career ERA+
And if you don’t like using ERA to measure pitchers, it’s not like Kershaw was getting hit around and executing magic to extricate himself. Thanks to an absurdly low .282 slugging% allowed, he was 3rd in OPS allowed to Lincecum and Carpenter, with Felix and Greinke the next two (and they were almost certainly more effective, due to the DH in the AL), then Vazquez, who was also probably more effective than OPS credits him, due to having a lower OPS. His sOPS+ (a very underutilized metric, since it park-adjusts the OPS stats against the pitcher – the pitching equivalent of OPS+ for hitters) was 59. For historical context, the guy to whom he’s drawn comparisons – Sandy Koufax – had a “60” sOPS+ in 1966 (his final season: 27-9, 1.73 and a Cy Young Award).
Kershaw will improve his walk rate:
Let’s suppose that Kershaw knocks off 33% of his walks, just taking 4.8 BB/9 down to 3.2 BB/9.
That would give him ratios of:
H/9: 6.3
BB/9: 3.2
K/9: 9.7 (9.0 used in P-I)
Plugging that into the B-R “P-I” tool, using 9.0 K/9 (just because), there have been 7 pitcher seasons (162+ IP) since 1901 where players have done that:
- Pedro Martinez (2000) 18-6, 1.74 11.78 K/9, 5.31 H/9, 1.33 BB/9
- Pedro Martinez (1997) 17-8, 1.9 11.37 K/9, 5.89 H/9, 2.5 BB/9
- Sandy Koufax (1964) 19-5, 1.74 9 K/9, 6.22 H/9, 2.14 BB/9
- Luis Tiant (1968) 21-9, 1.6 9.2 K/9, 5.3 H/9, 2.54 BB/9
- Johan Santana (2004) 20-6, 2.61 10.46 K/9, 6.16 H/9, 2.13 BB/9
- Mike Scott (1986) 18-10, 2.22 10 K/9, 5.95 H/9, 2.35 BB/9
- Sandy Koufax (1965) 26-8, 2.04 10.24 K/9, 5.79 H/9, 1.9 BB/9
If it’s run instead with these parameters: H/9: 7.0 BB/9: 3.5 K/9: 9.0, there are still only 34 pitcher-seasons which come up.
Looking at these things, it’s clear that either one of two things will happen with Kershaw, either he’ll reduce his walks and maintain his excellence, allowing him to put up some historically good seasons, or something will “give” – either the walks won’t improve, or he’ll be more hittable as he throws more strikes. Obviously, for people who look at Sabermetric staples for pitchers (BABIP and HR/FB%) are already expecting some regression in these stats in Kershaw’s future, so he’d have to pitch better (i.e. have better peripherals) to maintain similar effectiveness.
Kershaw will pitch more innings:
Okay, this one is a no-brainer, and the world will realize how great Kershaw is when he’s able to do this, if he stays healthy. It seems to be almost on the crazy side of optimistic to assume that Kershaw will improve his effectiveness at getting hitters out in any meaningful way, but if he trades some walks for more balls in play and more innings pitched, he’ll be as likely to garner Cy Young votes as anyone. As can be surmised from the high number of other precocious 21-year-olds listed above, we have to hope that his usage is managed well, and he’s allowed to grow into the high-IP starter the Dodgers want him to be.
Questions and comments for this article may be submitted to Rob McQuown at robmcquown@yahoo.com. Past articles for this author can be found under “Staff Writers” at the Baseball Daily Digest site.
