by Sam Waters
This post can also be seen at baseballanalyics.org here.
Last year, Josh Reddick slugged .457 with 7 homers in an 87-game stint with the Red Sox. Feeling confident in his outfield alternatives, Ben Cherington shipped Reddick to Oakland in December as the centerpiece of the Andrew Bailey trade. Following subsequent injuries to Bailey and a slew of Red Sox outfielders, Cherington must be regretting that move a lot right now. And that’s without even taking into account how well Reddick is playing this season. Reddick did flash some power in the minors, and this year those skills are translating to the big club. His fourteen homers slot him in at eighth in the MLB, while his .547 slugging percentage ranks twenty-first. We can get a better idea of how Reddick managed to raise his slugging percentage almost one hundred points in one year by looking at his splits across different pitch types.
Reddick has seen four types of pitches at least ten percent of the time over the last two years: fastballs, changeups, curveballs, and sliders. Last year, Reddick was about average in slugging on all four of these pitches. This year, he is performing at the same level on fastballs and a little better on sliders, but his jumps in slugging on changes and curves really stand out:
2012 Slugging Percentage v. Changeups and Curveballs
2011 Slugging Percentage v. Changeups and Curveballs
The heat maps above capture Reddick’s newfound prowess on these two pitches. He is now in the top twenty in baseball in slugging and home run percentage on both changeups and curveballs.
Unsurprisingly, in a season where Reddick is starting to flash major power on off-speed pitches, he ranks eighteenth among qualifying batters in percentage of fastballs seen. Last season he was about average in that category, so it seems that the league is adjusting to his improved performance on changes and curves. It still remains to be seen whether the league will adjust further to Reddick with an even heavier dose of fastballs, and how much this adjustment will affect him.
As a result of this pending adjustment and some regression to the mean, it would be unreasonable to expect Reddick to quite sustain his current pace. That being said, he does seem to have made legitimate improvements on off-speed pitches. Considering that he has never even played a full MLB season and is only 25 years old, these improvements could mark a permanent jump in Reddick’s development as a major league hitter.