Over the past 10 days or so, rumors have encircled the Detroit Tigers and the Chicago Cubs, centered around the potential trade of current Tigers center fielder Curtis Granderson to the Cubs. Chicago has made it a priority to find a center fielder with an above-average bat this winter, and with a career line of .272/.344/.484, Granderson certainly fits that bill.
However, some have peremptorily impugned the trade on two grounds: first, that Granderson would command too high a price in trade to Detroit; and second, that Granderson (like current Cubs outfielder and fellow left-handed hitter Kosuke Fukudome) cannot hit left-handed pitching.
Of the first objection, I won't speak further here, other than to say that I place far less stock in the hype surrounding Starlin Castro than do most Cubs fans, and would not hesitate to leverage his sky-high current value into a steal of a deal this offseason. Primarily, I want to focus upon the second issue.
It is, to be sure, a serious issue, and a damning allegation against Granderson's value, not least because it's true. In his career, Granderson has a .210/.270/.344 line against southpaws. Those offensive numbers, though accumulated in less than 700 career plate appearances, are untenable and represent a serious problem for which any team that acquires the young outfielder will have to have a solid solution.
The Cubs, however, have one unknown variable that could change the dynamic for Granderson, as well as his would-be outfield mate in Fukudome: newly acquired hitting coach Rudy Jaramillo.
Jaramillo signed on as the Cubs' hitting coach in October, after 15 seasons in the same role with the Texas Rangers. During those 15 years, Jaramillo (who played four years of Minor League ball in the 1970s, and who batted left-handed himself), oversaw one of the best offenses in the league.
Curious, however, I decided to dig deeper, and to try to decipher whether Jaramillo demonstrated any special ability to coach around large platoon splits among his troops.
To do so, I took a large-scale, statistical approach, rather than comb through his pupils one by one in search of anecdotes which I am quite sure would have exerted a selection bias.
Beginning with Jaramillo's debut season as Rangers hitting coach in 1995, I found the ratio of OPS (on-base plus slugging, a very crude estimate of a player's total offensive game) between having the platoon advantage and not having it for every season, and for both the Major Leagues and the Rangers specifically.
The results are encouraging. In ten of fifteen years, Jaramillo's charges better withstood platoon disadvantages than did the league as a whole. Two other seasons netted differences so small, I considered them a wash, given the influence of chance and the fact that Texas had a much smaller set of sample data, thereby making it more susceptible to random fluctuation.
To be more precise about the data I collected, here are the specifics. From 1995 to 2009, the ratio of performance when a batter has the platoon advantage rose fairly steadily for the league in general, from 1.036 to 1.075. That is, batters facing opposite-handed pitching did 7.5 percent better than when facing same-handed hurlers, in 2009. The 3.6 percent difference in 1995 was the lowest in my sample, league-wide.
For the Rangers, however, the ratio was consistently much smaller. In four season, Jaramillo's Rangers saw less than one percent decline when facing same-handed pitching.
Over the 15 years of Jaramillo's tenure, the Rangers averaged a drop-off of about 5.2 percent in those situations, compared to over 6.8 percent for the entire league. That difference may seem small, but in such an enormous sample size (15 years of Major League games), it is highly statistically significant.
At least, then, we can say with confidence that Jaramillo's teams have tended to succeed more often in situations where left-handed hitters face left-handed pitchers than is the league norm. It is not possible to entirely isolate Jaramillo's responsibility for that success.
Indeed, Cubs first baseman Derrek Lee might be inclined not to attribute any of that anomaly to his new coach: "I hate to say it, but a hitting coach is overrated," he said in October after the Cubs fired Von Joshua from that position. "It's more of a mental thing."
As far as it goes, however, the data supports the notion that Granderson would benefit from the tutelage of Jaramillo, and that Fukudome could also sustain more playing time against lefties in this new regime.
Jaramillo is not a witch doctor capable of making Alfonso Soriano hit a pitch above his belt, or resist one below the knees away. If Jim Hendry takes a chance this winter on Curtis Granderson, however, Jaramillo just might make him look like a genius.
Clear as day: One other note to aid those who support Granderson as a trade target. Granderson is a career .280/.360/.518 hitter during the day, substantially better figures than his .268/.336/.466 at night. Unless the Cubs' new owners get the 50 annual night games at home they want right away in 2010 (they won't), that could be a meaningful statistic.