Panda Hacks: Pablo Sandoval’s newfangled plate discipline

Watching Pablo Sandoval play baseball is a ton of fun. The Kung Fu Panda plays the game with a zeal that is infectious and visible. In addition to his unbridled enthusiasm, Sandoval rarely sees a pitch he doesn’t like, and it’s always fun to watch a batter with a Vladimir Guerrero approach to hitting.

And sometimes this happens.

His propensity for swinging has become something of a calling card for Sandoval. During his first season in major league baseball, Sandoval swung at a higher percentage of pitches outside of the strike zone (O-Swing percentage) than any other batter with at least 100 plate appearances. In each subsequent season, he has ranked in the top 10 O-Swing percentage.

Many hitters have had successful careers with a free-swinging approach, including Sandoval. Against right handed pitchers, Sandoval boasts a healthy slugging percentage on pitches in just about every location from his rookie season through 2014. The Brooks Baseball zone profile below elucidates this point.

Hack-happy Panda is awesome. However, we got a glimpse of just how awesome Sandoval can be with better plate discipline during the 2014 Postseason. According to Brooks Baseball, Sandoval swung at about 10% fewer pitches outside the strike zone during in the 2014 postseason than he did during the 2014 regular season. Sandoval’s postseason production was also markedly better by OBP and SLG. The chart below shows the difference between Sandoval’s regular season and playoff performances in 2014.

The ratio statistics indicate Sandoval was more productive when he swung at fewer pitches outside of the strike zone. This makes sense because those pitches are more difficult to hit effectively. Additionally, the opportunity cost associated with swinging at a ball is greater than swinging at a pitch that would be called a strike.

When the Boston Red Sox signed Sandoval to a 5-year, $95 million deal with a club option in year 6, they were likely hoping Sandoval would continue his judicious approach to pitch selection. Fortunately for the Red Sox, 2015 Sandoval is looking a lot like 2014 Postseason Sandoval. In the chart below, the first column displays how often Sandoval swings at pitches outside the strike zone (O-Swing percentage) during each regular season of his career and his 2014 postseason.

After about one month of regular season baseball, Sandoval’s offensive dashboard looks nearly identical to his 2014 postseason output. This is a great sign for the Red Sox and seems to indicate Sandoval’s improved plate discipline may not be an aberration.

But can we really draw conclusions after just one month of baseball? As sensible baseball fans, we need to be concerned with the hazards associated with small sample sizes. Such is life in April.

Typically, this would be a reasonable concern and regression to the mean, or something similar, would be necessary before we can trust the validity of this metric. However, it is well documented that plate discipline statistics normalize significantly quicker than other baseball statistics. In fact, plate discipline metrics usually normalize after only 50 plate appearances. Sam Miller reiterated this point recently on Baseball Prospectus’ daily podcast, Effectively Wild. This means we can have more confidence in Sandoval’s renaissance as a prudent batter. Take that, small sample sizes!

There are still several reasonable concerns surrounding the beloved third baseman. Notably, Jeff Zimmerman has alluded to the fact that players with higher body mass indexes do not age as gracefully as their leaner counterparts. Also, hitters rarely make significant leaps in their plate discipline metrics, and it is ever rarer to see this type of leap this late into a batter's career.

However, it does seem that Sandoval has become tangibly better at avoiding pitches outside the strike zone, and his offense has improved as a result.

Like a fine wine, the Panda is maturing beautifully.

. . .

Statistics and graphics courtesy of FanGraphs and Brooks Baseball.

Cody Callahan is a Contributor for Beyond the Box Score. You can follow him on Twitter at @codycallahan.