Andrew Koo joined BP's technical team in 2012, working to provide data and research for the site's content. Occasionally, he steps out from the backend shadows to write himself, including in two Baseball Prospectus annuals. He goes to school at the University of Waterloo in Ontario, Canada, where he divides his time between his math degree and watching baseball.
Understanding the relationship between plate discipline in the minors and future big-league success.
Not long ago, in the empty hours that fill scouts’ time between batting practice and the first pitch, I was speaking with (read: listening intently to) to an experienced scouting director. The topic of plate discipline came up. As anyone who closely follows the BP prospect team has figured out, I fall at the “extremely important” end of the spectrum when it comes to using plate discipline to evaluate prospects and predict their future success. Because of that, it didn’t take much prodding to get me to rave about a prospect I had recently seen from this scouting director’s system. The prospect, along with many strong skills, had a fantastic eye.
The scouting director’s response surprised me. He informed me his organization values plate discipline extremely highly, to the point of actually considering it a sixth tool (something we’ve seen the old-school camp dismiss in the past). I love the concept, but was stupefied because the organization in question is not one we typically think of as sabermetrically friendly. I assumed I was at a more extreme end of the spectrum on this topic, but here my views were accepted with arms open wider than I had anticipated.
Plate discipline, of course, is not a new concept in scouting. The way we view player value has brought about the current on-base renaissance within the big-league game, and that has had a trickle-down effect into the scouting world. With a better understanding of the value of on-base ability, we have changed how we evaluate prospects in some regards, at times excusing larger holes in a hit tool, for example, so long as it comes with strong on-base skills. The ability to avoid outs with better plate discipline can make up for some flaws in one’s ability to hit his way on base.
Thursday's recaps and the weekend preview from, well, basically the entire staff
The Thursday Takeaway
Not much separates the Tigers, A’s, and Angels this year, so every little advantage might help in October. With an 83 percent chance of winning its division entering play Thursday, one edge the Tigers will likely have is a relatively stress-free march from here to October. While the A’s (60 percent division odds) and the Angels (39 percent) will be beating each other into a pulp, the Tigers should be able to use the final two months to, for instance, rest Miguel Cabrera, as they did Thursday for just the second time all season. And they can start to think seriously about such October questions as: Would we really move Justin Verlander to the bullpen to make room for Rick Porcello?
Verlander pitched Wednesday and had one of his finest starts of the year, going seven innings while allowing two runs, striking out five, and walking one. Porcello, facing the same club in the same inhospitable pitching environment, bettered him Thursday, going seven innings while allowing one run, striking out five, and walking nobody. The effort lowered his season ERA to 3.09 and improved his team-best ERA+.
Last week, I talked about the offense required from first basemen to offset their negative positional adjustment. This week, we explore second base, whose occupants hit 20 points of True Average worse last season but produced the same total WARP. This demonstrates the defensive gap we’re familiar with while also illustrating the low offensive bar for second basemen. One needed to produce a TAv of only .261 while playing average defense to be a “league average” second baseman last year (league-average TAv is always scaled to be .260). Gregor Blanco personified the league average hitter in 2013—and he had the 114th-best TAv out of 141 qualified batters.
First base is the safe haven of offense-only players who need a position. Of the league’s 30 current first basemen (the team leaders of PAs at the position), eight primarily played different positions in the minor leagues. They’re the usual bat-first players whose gloves demanded a move: Miguel Cabrera, Chris Davis, Mark Reynolds, etc. For prospects, relegation to first base means they have nowhere else to go. If their hitting drops off in the slightest, they’ll have nothing else to compensate with, and they’ll be out of baseball.
After we released the PECOTA Top 100 prospects list last week, a few commenters remarked on PECOTA’s apparent catcher leanings. Eleven of them appeared on the list, some higher than nationally beloved prospects. How dare PECOTA! In comparison, Jason Parks’ top 101 featured eight catchers, suggesting a small discrepancy in the position distribution of PECOTA’s rankings.
When I reread Nate Silver’s PECOTA Takes on Prospects series, three themes emerged. One, minor-league statistics are pretty damn good at predicting future performance. Two, so many factors can derail a prediction, particularly for young prospects. Three—which doubles as a disclaimer for this series—I’m not Nate Silver. Apologies in advance.